examples: New board_usb
authorMichel Pollet <buserror@gmail.com>
Mon, 27 Feb 2012 14:21:16 +0000 (14:21 +0000)
committerMichel Pollet <buserror@gmail.com>
Mon, 27 Feb 2012 14:21:16 +0000 (14:21 +0000)
Automaticaly tries to build the vhci libraries
TODO: Make the whole simavr build work even if the vhci
      compile fails, or is not linux

By: Torbjorn Tyridal <ttyridal@gmail.com>
Signed-off-by: Michel Pollet <buserror@gmail.com>
examples/board_usb/.gitignore [new file with mode: 0644]
examples/board_usb/Makefile [new file with mode: 0644]
examples/board_usb/README [new file with mode: 0644]
examples/board_usb/at90usb162_cdc_loopback.c [new file with mode: 0644]
examples/board_usb/at90usb162_cdc_loopback.h [new file with mode: 0644]
examples/board_usb/simusb.c [new file with mode: 0644]

diff --git a/examples/board_usb/.gitignore b/examples/board_usb/.gitignore
new file mode 100644 (file)
index 0000000..04e1d75
--- /dev/null
@@ -0,0 +1 @@
+simusb_flash.bin
diff --git a/examples/board_usb/Makefile b/examples/board_usb/Makefile
new file mode 100644 (file)
index 0000000..410b9d4
--- /dev/null
@@ -0,0 +1,63 @@
+# 
+#      Copyright 2012 Torbjorn Tyridal <ttyridal@gmail.com>
+#
+#      This file is part of simavr.
+#
+#      simavr is free software: you can redistribute it and/or modify
+#      it under the terms of the GNU General Public License as published by
+#      the Free Software Foundation, either version 3 of the License, or
+#      (at your option) any later version.
+#
+#      simavr is distributed in the hope that it will be useful,
+#      but WITHOUT ANY WARRANTY; without even the implied warranty of
+#      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#      GNU General Public License for more details.
+#
+#      You should have received a copy of the GNU General Public License
+#      along with simavr.  If not, see <http://www.gnu.org/licenses/>.
+
+target=        simusb
+firm_src = at90usb162_cdc_loopback.c
+firmware = ${firm_src:.c=.hex}
+simavr = ../../
+
+SHELL   = /bin/bash
+
+IPATH = .
+IPATH += ../parts
+IPATH += ../vhci/include
+IPATH += ../vhci
+IPATH += ${simavr}/include
+IPATH += ${simavr}/simavr/sim
+#IPATH += /usr/local/include
+
+VPATH = .
+VPATH += ../parts
+
+LDFLAGS += -lpthread -lusb_vhci -L../vhci/lib
+
+all: obj ${firmware} ${target}
+
+include ${simavr}/Makefile.common
+
+board = ${OBJ}/${target}.elf
+
+${board} : ${OBJ}/vhci_usb.o
+${board} : ${OBJ}/${target}.o
+
+../vhci/lib/libusb_vhci.a:
+       @echo -n "BUILDIN $@ "
+       @{ make -j -C ../vhci >/tmp/vhci.build.log 2>&1 || \
+               { echo "ERROR check /tmp/vhci.build.log"; exit 1; }; } && \
+                       echo " Done" 
+
+vhci : ../vhci/lib/libusb_vhci.a 
+
+clean-vhci:
+       make -C ../vhci clean
+
+${target}: vhci ${board}
+       @echo $@ done
+
+clean: clean-${OBJ} clean-vhci
+       rm -rf *.a *.axf *.hex ${target} *.vcd
diff --git a/examples/board_usb/README b/examples/board_usb/README
new file mode 100644 (file)
index 0000000..0db5550
--- /dev/null
@@ -0,0 +1,45 @@
+This will bridge the usb avr to the vhci-usb virtual usb host.
+
+You'll need vhci-usb and vhci-usb-lib to build and use it.
+(http://sourceforge.net/projects/usb-vhci/)
+
+When setup, your avr project will connect to the linux usb system
+as a real device.
+
+BUILDING usb-vhci
+-----------------
+git://usb-vhci.git.sourceforge.net/gitroot/usb-vhci/vhci_hcd
+
+The driver doesn't compile on recent linux kernels.
+(commit 203800f0 Mon Apr 4)
+0001-SPIN_LOCK_UNLOCKED-has-been-depreciated.patch
+and
+0002-need-transaction-translator.patch            
+should fix that.
+
+then simply "make && make install"
+
+might need to copy the api header file:
+mkdir -p /usr/local/include/linux
+sudo cp usb-vhci.h /usr/local/include/linux
+
+
+BUILDING libusb_vhci
+--------------------
+git://usb-vhci.git.sourceforge.net/gitroot/usb-vhci/libusb_vhci
+
+This was a little more troublesome, but I didn't care to figure it out.
+with libusb_vhci trunk (commit 5927f39a Sun Mar 27)
+
+add
+0001-Comment-out-function-that-doesn-t-compile.patch
+patch to remove that won't compile (and we don't use)
+then:
+cd src
+gcc -c libusb_vhci.c 
+ar rcs libusb_vhci.a libusb_vhci.o
+sudo cp libusb_vhci.a /usr/local/lib
+mkdir -p /usr/local/include/linux
+sudo cp libusb_vhci.h /usr/local/include/linux
+
+Gives us what we need
diff --git a/examples/board_usb/at90usb162_cdc_loopback.c b/examples/board_usb/at90usb162_cdc_loopback.c
new file mode 100644 (file)
index 0000000..ae6dc40
--- /dev/null
@@ -0,0 +1,959 @@
+/* vim: set sts=4:sw=4:ts=4:noexpandtab
+ *
+ * USB Serial Example for Teensy USB Development Board
+ * http://www.pjrc.com/teensy/usb_serial.html
+ * Copyright (c) 2008,2010,2011 PJRC.COM, LLC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+// Version 1.0: Initial Release
+// Version 1.1: support Teensy++
+// Version 1.2: fixed usb_serial_available
+// Version 1.3: added transmit bandwidth test
+// Version 1.4: added usb_serial_write
+// Version 1.5: add support for Teensy 2.0
+// Version 1.6: fix zero length packet bug
+// Version 1.7: fix usb_serial_set_control
+
+#define USB_SERIAL_PRIVATE_INCLUDE
+#include "at90usb162_cdc_loopback.h"
+
+/**************************************************************************
+ *
+ *  Configurable Options
+ *
+ **************************************************************************/
+
+// You can change these to give your code its own name.  On Windows,
+// these are only used before an INF file (driver install) is loaded.
+#define STR_MANUFACTURER       L"Your Name"
+#define STR_PRODUCT            L"USB Serial"
+
+// All USB serial devices are supposed to have a serial number
+// (according to Microsoft).  On windows, a new COM port is created
+// for every unique serial/vendor/product number combination.  If
+// you program 2 identical boards with 2 different serial numbers
+// and they are assigned COM7 and COM8, each will always get the
+// same COM port number because Windows remembers serial numbers.
+//
+// On Mac OS-X, a device file is created automatically which
+// incorperates the serial number, eg, /dev/cu-usbmodem12341
+//
+// Linux by default ignores the serial number, and creates device
+// files named /dev/ttyACM0, /dev/ttyACM1... in the order connected.
+// Udev rules (in /etc/udev/rules.d) can define persistent device
+// names linked to this serial number, as well as permissions, owner
+// and group settings.
+#define STR_SERIAL_NUMBER      L"12345"
+
+// Mac OS-X and Linux automatically load the correct drivers.  On
+// Windows, even though the driver is supplied by Microsoft, an
+// INF file is needed to load the driver.  These numbers need to
+// match the INF file.
+#define VENDOR_ID              0x16C0
+#define PRODUCT_ID             0x047A
+
+// When you write data, it goes into a USB endpoint buffer, which
+// is transmitted to the PC when it becomes full, or after a timeout
+// with no more writes.  Even if you write in exactly packet-size
+// increments, this timeout is used to send a "zero length packet"
+// that tells the PC no more data is expected and it should pass
+// any buffered data to the application that may be waiting.  If
+// you want data sent immediately, call usb_serial_flush_output().
+#define TRANSMIT_FLUSH_TIMEOUT 5   /* in milliseconds */
+
+// If the PC is connected but not "listening", this is the length
+// of time before usb_serial_getchar() returns with an error.  This
+// is roughly equivilant to a real UART simply transmitting the
+// bits on a wire where nobody is listening, except you get an error
+// code which you can ignore for serial-like discard of data, or
+// use to know your data wasn't sent.
+#define TRANSMIT_TIMEOUT       25   /* in milliseconds */
+
+// USB devices are supposed to implment a halt feature, which is
+// rarely (if ever) used.  If you comment this line out, the halt
+// code will be removed, saving 116 bytes of space (gcc 4.3.0).
+// This is not strictly USB compliant, but works with all major
+// operating systems.
+#define SUPPORT_ENDPOINT_HALT
+
+
+
+/**************************************************************************
+ *
+ *  Endpoint Buffer Configuration
+ *
+ **************************************************************************/
+
+// These buffer sizes are best for most applications, but perhaps if you
+// want more buffering on some endpoint at the expense of others, this
+// is where you can make such changes.  The AT90USB162 has only 176 bytes
+// of DPRAM (USB buffers) and only endpoints 3 & 4 can double buffer.
+
+#define ENDPOINT0_SIZE         16
+#define CDC_ACM_ENDPOINT       2
+#define CDC_RX_ENDPOINT                3
+#define CDC_TX_ENDPOINT                4
+#if defined(__AVR_AT90USB162__)
+#define CDC_ACM_SIZE           16
+#define CDC_ACM_BUFFER         EP_SINGLE_BUFFER
+#define CDC_RX_SIZE            32
+#define CDC_RX_BUFFER          EP_DOUBLE_BUFFER
+#define CDC_TX_SIZE            32
+#define CDC_TX_BUFFER          EP_DOUBLE_BUFFER
+#else
+#define CDC_ACM_SIZE           16
+#define CDC_ACM_BUFFER         EP_SINGLE_BUFFER
+#define CDC_RX_SIZE            64
+#define CDC_RX_BUFFER          EP_DOUBLE_BUFFER
+#define CDC_TX_SIZE            64
+#define CDC_TX_BUFFER          EP_DOUBLE_BUFFER
+#endif
+
+static const uint8_t PROGMEM endpoint_config_table[] = {
+       0,
+       1, EP_TYPE_INTERRUPT_IN,  EP_SIZE(CDC_ACM_SIZE) | CDC_ACM_BUFFER,
+       1, EP_TYPE_BULK_OUT,      EP_SIZE(CDC_RX_SIZE) | CDC_RX_BUFFER,
+       1, EP_TYPE_BULK_IN,       EP_SIZE(CDC_TX_SIZE) | CDC_TX_BUFFER
+};
+
+
+/**************************************************************************
+ *
+ *  Descriptor Data
+ *
+ **************************************************************************/
+
+// Descriptors are the data that your computer reads when it auto-detects
+// this USB device (called "enumeration" in USB lingo).  The most commonly
+// changed items are editable at the top of this file.  Changing things
+// in here should only be done by those who've read chapter 9 of the USB
+// spec and relevant portions of any USB class specifications!
+
+static uint8_t PROGMEM device_descriptor[] = {
+       18,                                     // bLength
+       1,                                      // bDescriptorType
+       0x00, 0x02,                             // bcdUSB
+       2,                                      // bDeviceClass
+       0,                                      // bDeviceSubClass
+       0,                                      // bDeviceProtocol
+       ENDPOINT0_SIZE,                         // bMaxPacketSize0
+       LSB(VENDOR_ID), MSB(VENDOR_ID),         // idVendor
+       LSB(PRODUCT_ID), MSB(PRODUCT_ID),       // idProduct
+       0x00, 0x01,                             // bcdDevice
+       1,                                      // iManufacturer
+       2,                                      // iProduct
+       3,                                      // iSerialNumber
+       1                                       // bNumConfigurations
+};
+
+#define CONFIG1_DESC_SIZE (9+9+5+5+4+5+7+9+7+7)
+static uint8_t PROGMEM config1_descriptor[CONFIG1_DESC_SIZE] = {
+       // configuration descriptor, USB spec 9.6.3, page 264-266, Table 9-10
+       9,                                      // bLength;
+       2,                                      // bDescriptorType;
+       LSB(CONFIG1_DESC_SIZE),                 // wTotalLength
+       MSB(CONFIG1_DESC_SIZE),
+       2,                                      // bNumInterfaces
+       1,                                      // bConfigurationValue
+       0,                                      // iConfiguration
+       0xC0,                                   // bmAttributes
+       50,                                     // bMaxPower
+       // interface descriptor, USB spec 9.6.5, page 267-269, Table 9-12
+       9,                                      // bLength
+       4,                                      // bDescriptorType
+       0,                                      // bInterfaceNumber
+       0,                                      // bAlternateSetting
+       1,                                      // bNumEndpoints
+       0x02,                                   // bInterfaceClass
+       0x02,                                   // bInterfaceSubClass
+       0x01,                                   // bInterfaceProtocol
+       0,                                      // iInterface
+       // CDC Header Functional Descriptor, CDC Spec 5.2.3.1, Table 26
+       5,                                      // bFunctionLength
+       0x24,                                   // bDescriptorType
+       0x00,                                   // bDescriptorSubtype
+       0x10, 0x01,                             // bcdCDC
+       // Call Management Functional Descriptor, CDC Spec 5.2.3.2, Table 27
+       5,                                      // bFunctionLength
+       0x24,                                   // bDescriptorType
+       0x01,                                   // bDescriptorSubtype
+       0x01,                                   // bmCapabilities
+       1,                                      // bDataInterface
+       // Abstract Control Management Functional Descriptor, CDC Spec 5.2.3.3, Table 28
+       4,                                      // bFunctionLength
+       0x24,                                   // bDescriptorType
+       0x02,                                   // bDescriptorSubtype
+       0x06,                                   // bmCapabilities
+       // Union Functional Descriptor, CDC Spec 5.2.3.8, Table 33
+       5,                                      // bFunctionLength
+       0x24,                                   // bDescriptorType
+       0x06,                                   // bDescriptorSubtype
+       0,                                      // bMasterInterface
+       1,                                      // bSlaveInterface0
+       // endpoint descriptor, USB spec 9.6.6, page 269-271, Table 9-13
+       7,                                      // bLength
+       5,                                      // bDescriptorType
+       CDC_ACM_ENDPOINT | 0x80,                // bEndpointAddress
+       0x03,                                   // bmAttributes (0x03=intr)
+       CDC_ACM_SIZE, 0,                        // wMaxPacketSize
+       64,                                     // bInterval
+       // interface descriptor, USB spec 9.6.5, page 267-269, Table 9-12
+       9,                                      // bLength
+       4,                                      // bDescriptorType
+       1,                                      // bInterfaceNumber
+       0,                                      // bAlternateSetting
+       2,                                      // bNumEndpoints
+       0x0A,                                   // bInterfaceClass
+       0x00,                                   // bInterfaceSubClass
+       0x00,                                   // bInterfaceProtocol
+       0,                                      // iInterface
+       // endpoint descriptor, USB spec 9.6.6, page 269-271, Table 9-13
+       7,                                      // bLength
+       5,                                      // bDescriptorType
+       CDC_RX_ENDPOINT,                        // bEndpointAddress
+       0x02,                                   // bmAttributes (0x02=bulk)
+       CDC_RX_SIZE, 0,                         // wMaxPacketSize
+       0,                                      // bInterval
+       // endpoint descriptor, USB spec 9.6.6, page 269-271, Table 9-13
+       7,                                      // bLength
+       5,                                      // bDescriptorType
+       CDC_TX_ENDPOINT | 0x80,                 // bEndpointAddress
+       0x02,                                   // bmAttributes (0x02=bulk)
+       CDC_TX_SIZE, 0,                         // wMaxPacketSize
+       0                                       // bInterval
+};
+
+// If you're desperate for a little extra code memory, these strings
+// can be completely removed if iManufacturer, iProduct, iSerialNumber
+// in the device desciptor are changed to zeros.
+struct usb_string_descriptor_struct {
+       uint8_t bLength;
+       uint8_t bDescriptorType;
+       int16_t wString[];
+};
+static struct usb_string_descriptor_struct PROGMEM string0 = {
+       4,
+       3,
+       {0x0409}
+};
+static struct usb_string_descriptor_struct PROGMEM string1 = {
+       sizeof(STR_MANUFACTURER),
+       3,
+       STR_MANUFACTURER
+};
+static struct usb_string_descriptor_struct PROGMEM string2 = {
+       sizeof(STR_PRODUCT),
+       3,
+       STR_PRODUCT
+};
+static struct usb_string_descriptor_struct PROGMEM string3 = {
+       sizeof(STR_SERIAL_NUMBER),
+       3,
+       STR_SERIAL_NUMBER
+};
+
+// This table defines which descriptor data is sent for each specific
+// request from the host (in wValue and wIndex).
+static struct descriptor_list_struct {
+       uint16_t        wValue;
+       uint16_t        wIndex;
+       const uint8_t   *addr;
+       uint8_t         length;
+} PROGMEM descriptor_list[] = {
+       {0x0100, 0x0000, device_descriptor, sizeof(device_descriptor)},
+       {0x0200, 0x0000, config1_descriptor, sizeof(config1_descriptor)},
+       {0x0300, 0x0000, (const uint8_t *)&string0, 4},
+       {0x0301, 0x0409, (const uint8_t *)&string1, sizeof(STR_MANUFACTURER)},
+       {0x0302, 0x0409, (const uint8_t *)&string2, sizeof(STR_PRODUCT)},
+       {0x0303, 0x0409, (const uint8_t *)&string3, sizeof(STR_SERIAL_NUMBER)}
+};
+#define NUM_DESC_LIST (sizeof(descriptor_list)/sizeof(struct descriptor_list_struct))
+
+
+/**************************************************************************
+ *
+ *  Variables - these are the only non-stack RAM usage
+ *
+ **************************************************************************/
+
+// zero when we are not configured, non-zero when enumerated
+static volatile uint8_t usb_configuration=0;
+
+// the time remaining before we transmit any partially full
+// packet, or send a zero length packet.
+static volatile uint8_t transmit_flush_timer=0;
+static uint8_t transmit_previous_timeout=0;
+
+// serial port settings (baud rate, control signals, etc) set
+// by the PC.  These are ignored, but kept in RAM.
+static uint8_t cdc_line_coding[7]={0x00, 0xE1, 0x00, 0x00, 0x00, 0x00, 0x08};
+static uint8_t cdc_line_rtsdtr=0;
+
+
+/**************************************************************************
+ *
+ *  Public Functions - these are the API intended for the user
+ *
+ **************************************************************************/
+
+// initialize USB serial
+void usb_init(void)
+{
+       sei();
+       HW_CONFIG();
+               USB_FREEZE();                           // enable USB
+               PLL_CONFIG();                           // config PLL, 16 MHz xtal
+               while (!(PLLCSR & (1<<PLOCK))) ;        // wait for PLL lock
+               USB_CONFIG();                           // start USB clock
+               UDCON = 0;                              // enable attach resistor
+       usb_configuration = 0;
+       cdc_line_rtsdtr = 0;
+               UDIEN = (1<<EORSTE)|(1<<SOFE);
+}
+
+// return 0 if the USB is not configured, or the configuration
+// number selected by the HOST
+uint8_t usb_configured(void)
+{
+       return usb_configuration;
+}
+
+// get the next character, or -1 if nothing received
+int16_t usb_serial_getchar(void)
+{
+       uint8_t c, intr_state;
+
+       // interrupts are disabled so these functions can be
+       // used from the main program or interrupt context,
+       // even both in the same program!
+       intr_state = SREG;
+       cli();
+       if (!usb_configuration) {
+               SREG = intr_state;
+               return -1;
+       }
+       UENUM = CDC_RX_ENDPOINT;
+       retry:
+       c = UEINTX;
+       if (!(c & (1<<RWAL))) {
+               // no data in buffer
+               if (c & (1<<RXOUTI)) {
+                       UEINTX = 0x6B;
+                       goto retry;
+               }
+               SREG = intr_state;
+               return -1;
+       }
+       // take one byte out of the buffer
+       c = UEDATX;
+       // if buffer completely used, release it
+       if (!(UEINTX & (1<<RWAL))) UEINTX = 0x6B;
+       SREG = intr_state;
+       return c;
+}
+
+// number of bytes available in the receive buffer
+uint8_t usb_serial_available(void)
+{
+       uint8_t n=0, i, intr_state;
+
+       intr_state = SREG;
+       cli();
+       if (usb_configuration) {
+               UENUM = CDC_RX_ENDPOINT;
+               n = UEBCLX;
+               if (!n) {
+                       i = UEINTX;
+                       if (i & (1<<RXOUTI) && !(i & (1<<RWAL))) UEINTX = 0x6B;
+               }
+       }
+       SREG = intr_state;
+       return n;
+}
+
+// discard any buffered input
+void usb_serial_flush_input(void)
+{
+       uint8_t intr_state;
+
+       if (usb_configuration) {
+               intr_state = SREG;
+               cli();
+               UENUM = CDC_RX_ENDPOINT;
+               while ((UEINTX & (1<<RWAL))) {
+                       UEINTX = 0x6B;
+               }
+               SREG = intr_state;
+       }
+}
+
+// transmit a character.  0 returned on success, -1 on error
+int8_t usb_serial_putchar(uint8_t c)
+{
+       uint8_t timeout, intr_state;
+
+       // if we're not online (enumerated and configured), error
+       if (!usb_configuration) return -1;
+       // interrupts are disabled so these functions can be
+       // used from the main program or interrupt context,
+       // even both in the same program!
+       intr_state = SREG;
+       cli();
+       UENUM = CDC_TX_ENDPOINT;
+       // if we gave up due to timeout before, don't wait again
+       if (transmit_previous_timeout) {
+               if (!(UEINTX & (1<<RWAL))) {
+                       SREG = intr_state;
+                       return -1;
+               }
+               transmit_previous_timeout = 0;
+       }
+       // wait for the FIFO to be ready to accept data
+       timeout = UDFNUML + TRANSMIT_TIMEOUT;
+       while (1) {
+               // are we ready to transmit?
+               if (UEINTX & (1<<RWAL)) break;
+               SREG = intr_state;
+               // have we waited too long?  This happens if the user
+               // is not running an application that is listening
+               if (UDFNUML == timeout) {
+                       transmit_previous_timeout = 1;
+                       return -1;
+               }
+               // has the USB gone offline?
+               if (!usb_configuration) return -1;
+               // get ready to try checking again
+               intr_state = SREG;
+               cli();
+               UENUM = CDC_TX_ENDPOINT;
+       }
+       // actually write the byte into the FIFO
+       UEDATX = c;
+       // if this completed a packet, transmit it now!
+       if (!(UEINTX & (1<<RWAL))) UEINTX = 0x3A;
+       transmit_flush_timer = TRANSMIT_FLUSH_TIMEOUT;
+       SREG = intr_state;
+       return 0;
+}
+
+
+// transmit a character, but do not wait if the buffer is full,
+//   0 returned on success, -1 on buffer full or error
+int8_t usb_serial_putchar_nowait(uint8_t c)
+{
+       uint8_t intr_state;
+
+       if (!usb_configuration) return -1;
+       intr_state = SREG;
+       cli();
+       UENUM = CDC_TX_ENDPOINT;
+       if (!(UEINTX & (1<<RWAL))) {
+               // buffer is full
+               SREG = intr_state;
+               return -1;
+       }
+       // actually write the byte into the FIFO
+       UEDATX = c;
+               // if this completed a packet, transmit it now!
+       if (!(UEINTX & (1<<RWAL))) UEINTX = 0x3A;
+       transmit_flush_timer = TRANSMIT_FLUSH_TIMEOUT;
+       SREG = intr_state;
+       return 0;
+}
+
+// transmit a buffer.
+//  0 returned on success, -1 on error
+// This function is optimized for speed!  Each call takes approx 6.1 us overhead
+// plus 0.25 us per byte.  12 Mbit/sec USB has 8.67 us per-packet overhead and
+// takes 0.67 us per byte.  If called with 64 byte packet-size blocks, this function
+// can transmit at full USB speed using 43% CPU time.  The maximum theoretical speed
+// is 19 packets per USB frame, or 1216 kbytes/sec.  However, bulk endpoints have the
+// lowest priority, so any other USB devices will likely reduce the speed.  Speed
+// can also be limited by how quickly the PC-based software reads data, as the host
+// controller in the PC will not allocate bandwitdh without a pending read request.
+// (thanks to Victor Suarez for testing and feedback and initial code)
+
+int8_t usb_serial_write(const uint8_t *buffer, uint16_t size)
+{
+       uint8_t timeout, intr_state, write_size;
+
+       // if we're not online (enumerated and configured), error
+       if (!usb_configuration) return -1;
+       // interrupts are disabled so these functions can be
+       // used from the main program or interrupt context,
+       // even both in the same program!
+       intr_state = SREG;
+       cli();
+       UENUM = CDC_TX_ENDPOINT;
+       // if we gave up due to timeout before, don't wait again
+       if (transmit_previous_timeout) {
+               if (!(UEINTX & (1<<RWAL))) {
+                       SREG = intr_state;
+                       return -1;
+               }
+               transmit_previous_timeout = 0;
+       }
+       // each iteration of this loop transmits a packet
+       while (size) {
+               // wait for the FIFO to be ready to accept data
+               timeout = UDFNUML + TRANSMIT_TIMEOUT;
+               while (1) {
+                       // are we ready to transmit?
+                       if (UEINTX & (1<<RWAL)) break;
+                       SREG = intr_state;
+                       // have we waited too long?  This happens if the user
+                       // is not running an application that is listening
+                       if (UDFNUML == timeout) {
+                               transmit_previous_timeout = 1;
+                               return -1;
+                       }
+                       // has the USB gone offline?
+                       if (!usb_configuration) return -1;
+                       // get ready to try checking again
+                       intr_state = SREG;
+                       cli();
+                       UENUM = CDC_TX_ENDPOINT;
+               }
+
+               // compute how many bytes will fit into the next packet
+               write_size = CDC_TX_SIZE - UEBCLX;
+               if (write_size > size) write_size = size;
+               size -= write_size;
+
+               // write the packet
+               switch (write_size) {
+                       #if (CDC_TX_SIZE == 64)
+                       case 64: UEDATX = *buffer++;
+                       case 63: UEDATX = *buffer++;
+                       case 62: UEDATX = *buffer++;
+                       case 61: UEDATX = *buffer++;
+                       case 60: UEDATX = *buffer++;
+                       case 59: UEDATX = *buffer++;
+                       case 58: UEDATX = *buffer++;
+                       case 57: UEDATX = *buffer++;
+                       case 56: UEDATX = *buffer++;
+                       case 55: UEDATX = *buffer++;
+                       case 54: UEDATX = *buffer++;
+                       case 53: UEDATX = *buffer++;
+                       case 52: UEDATX = *buffer++;
+                       case 51: UEDATX = *buffer++;
+                       case 50: UEDATX = *buffer++;
+                       case 49: UEDATX = *buffer++;
+                       case 48: UEDATX = *buffer++;
+                       case 47: UEDATX = *buffer++;
+                       case 46: UEDATX = *buffer++;
+                       case 45: UEDATX = *buffer++;
+                       case 44: UEDATX = *buffer++;
+                       case 43: UEDATX = *buffer++;
+                       case 42: UEDATX = *buffer++;
+                       case 41: UEDATX = *buffer++;
+                       case 40: UEDATX = *buffer++;
+                       case 39: UEDATX = *buffer++;
+                       case 38: UEDATX = *buffer++;
+                       case 37: UEDATX = *buffer++;
+                       case 36: UEDATX = *buffer++;
+                       case 35: UEDATX = *buffer++;
+                       case 34: UEDATX = *buffer++;
+                       case 33: UEDATX = *buffer++;
+                       #endif
+                       #if (CDC_TX_SIZE >= 32)
+                       case 32: UEDATX = *buffer++;
+                       case 31: UEDATX = *buffer++;
+                       case 30: UEDATX = *buffer++;
+                       case 29: UEDATX = *buffer++;
+                       case 28: UEDATX = *buffer++;
+                       case 27: UEDATX = *buffer++;
+                       case 26: UEDATX = *buffer++;
+                       case 25: UEDATX = *buffer++;
+                       case 24: UEDATX = *buffer++;
+                       case 23: UEDATX = *buffer++;
+                       case 22: UEDATX = *buffer++;
+                       case 21: UEDATX = *buffer++;
+                       case 20: UEDATX = *buffer++;
+                       case 19: UEDATX = *buffer++;
+                       case 18: UEDATX = *buffer++;
+                       case 17: UEDATX = *buffer++;
+                       #endif
+                       #if (CDC_TX_SIZE >= 16)
+                       case 16: UEDATX = *buffer++;
+                       case 15: UEDATX = *buffer++;
+                       case 14: UEDATX = *buffer++;
+                       case 13: UEDATX = *buffer++;
+                       case 12: UEDATX = *buffer++;
+                       case 11: UEDATX = *buffer++;
+                       case 10: UEDATX = *buffer++;
+                       case  9: UEDATX = *buffer++;
+                       #endif
+                       case  8: UEDATX = *buffer++;
+                       case  7: UEDATX = *buffer++;
+                       case  6: UEDATX = *buffer++;
+                       case  5: UEDATX = *buffer++;
+                       case  4: UEDATX = *buffer++;
+                       case  3: UEDATX = *buffer++;
+                       case  2: UEDATX = *buffer++;
+                       default:
+                       case  1: UEDATX = *buffer++;
+                       case  0: break;
+               }
+               // if this completed a packet, transmit it now!
+               if (!(UEINTX & (1<<RWAL))) UEINTX = 0x3A;
+               transmit_flush_timer = TRANSMIT_FLUSH_TIMEOUT;
+               SREG = intr_state;
+       }
+       return 0;
+}
+
+
+// immediately transmit any buffered output.
+// This doesn't actually transmit the data - that is impossible!
+// USB devices only transmit when the host allows, so the best
+// we can do is release the FIFO buffer for when the host wants it
+void usb_serial_flush_output(void)
+{
+       uint8_t intr_state;
+
+       intr_state = SREG;
+       cli();
+       if (transmit_flush_timer) {
+               UENUM = CDC_TX_ENDPOINT;
+               UEINTX = 0x3A;
+               transmit_flush_timer = 0;
+       }
+       SREG = intr_state;
+}
+
+// functions to read the various async serial settings.  These
+// aren't actually used by USB at all (communication is always
+// at full USB speed), but they are set by the host so we can
+// set them properly if we're converting the USB to a real serial
+// communication
+// uint32_t usb_serial_get_baud(void)
+// {
+//     return *(uint32_t *)cdc_line_coding;
+// }
+uint8_t usb_serial_get_stopbits(void)
+{
+       return cdc_line_coding[4];
+}
+uint8_t usb_serial_get_paritytype(void)
+{
+       return cdc_line_coding[5];
+}
+uint8_t usb_serial_get_numbits(void)
+{
+       return cdc_line_coding[6];
+}
+uint8_t usb_serial_get_control(void)
+{
+       return cdc_line_rtsdtr;
+}
+// write the control signals, DCD, DSR, RI, etc
+// There is no CTS signal.  If software on the host has transmitted
+// data to you but you haven't been calling the getchar function,
+// it remains buffered (either here or on the host) and can not be
+// lost because you weren't listening at the right time, like it
+// would in real serial communication.
+int8_t usb_serial_set_control(uint8_t signals)
+{
+       uint8_t intr_state;
+
+       intr_state = SREG;
+       cli();
+       if (!usb_configuration) {
+               // we're not enumerated/configured
+               SREG = intr_state;
+               return -1;
+       }
+
+       UENUM = CDC_ACM_ENDPOINT;
+       if (!(UEINTX & (1<<RWAL))) {
+               // unable to write
+               // TODO; should this try to abort the previously
+               // buffered message??
+               SREG = intr_state;
+               return -1;
+       }
+       UEDATX = 0xA1;
+       UEDATX = 0x20;
+       UEDATX = 0;
+       UEDATX = 0;
+       UEDATX = 0; // 0 seems to work nicely.  what if this is 1??
+       UEDATX = 0;
+       UEDATX = 1;
+       UEDATX = 0;
+       UEDATX = signals;
+       UEINTX = 0x3A;
+       SREG = intr_state;
+       return 0;
+}
+
+
+
+/**************************************************************************
+ *
+ *  Private Functions - not intended for general user consumption....
+ *
+ **************************************************************************/
+
+
+// USB Device Interrupt - handle all device-level events
+// the transmit buffer flushing is triggered by the start of frame
+//
+ISR(USB_GEN_vect, ISR_BLOCK)
+{
+       uint8_t intbits, t;
+               intbits = UDINT;
+               UDINT = 0;
+       if (intbits & (1<<EORSTI)) {
+               UENUM = 0;
+               UECONX = 1;
+               UECFG0X = EP_TYPE_CONTROL;
+               UECFG1X = EP_SIZE(ENDPOINT0_SIZE) | EP_SINGLE_BUFFER;
+               UEIENX = (1<<RXSTPE);
+               usb_configuration = 0;
+               cdc_line_rtsdtr = 0;
+       }
+       if (intbits & (1<<SOFI)) {
+               if (usb_configuration) {
+                       t = transmit_flush_timer;
+                       if (t) {
+                               transmit_flush_timer = --t;
+                               if (!t) {
+                                       UENUM = CDC_TX_ENDPOINT;
+                                       UEINTX = 0x3A;
+                               }
+                       }
+               }
+       }
+}
+
+
+// Misc functions to wait for ready and send/receive packets
+static inline void usb_wait_in_ready(void)
+{
+       while (!(UEINTX & (1<<TXINI))) ;
+}
+static inline void usb_send_in(void)
+{
+       UEINTX = ~(1<<TXINI);
+}
+static inline void usb_wait_receive_out(void)
+{
+       while (!(UEINTX & (1<<RXOUTI))) ;
+}
+static inline void usb_ack_out(void)
+{
+       UEINTX = ~(1<<RXOUTI);
+}
+
+
+
+// USB Endpoint Interrupt - endpoint 0 is handled here.  The
+// other endpoints are manipulated by the user-callable
+// functions, and the start-of-frame interrupt.
+//
+ISR(USB_COM_vect, ISR_BLOCK)
+{
+       uint8_t intbits;
+       const uint8_t *list;
+       const uint8_t *cfg;
+       uint8_t i, n, len, en;
+       uint8_t *p;
+       uint8_t bmRequestType;
+       uint8_t bRequest;
+       uint16_t wValue;
+       uint16_t wIndex;
+       uint16_t wLength;
+       uint16_t desc_val;
+       const uint8_t *desc_addr;
+       uint8_t desc_length;
+
+       UENUM = 0;
+       intbits = UEINTX;
+       if (intbits & (1<<RXSTPI)) {
+               bmRequestType = UEDATX;
+               bRequest = UEDATX;
+               wValue = UEDATX;
+               wValue |= (UEDATX << 8);
+               wIndex = UEDATX;
+               wIndex |= (UEDATX << 8);
+               wLength = UEDATX;
+               wLength |= (UEDATX << 8);
+               UEINTX = ~((1<<RXSTPI) | (1<<RXOUTI) | (1<<TXINI));
+               if (bRequest == GET_DESCRIPTOR) {
+                       list = (const uint8_t *)descriptor_list;
+                       for (i=0; ; i++) {
+                               if (i >= NUM_DESC_LIST) {
+                                       UECONX = (1<<STALLRQ)|(1<<EPEN);  //stall
+                                       return;
+                               }
+                               desc_val = pgm_read_word(list);
+                               if (desc_val != wValue) {
+                                       list += sizeof(struct descriptor_list_struct);
+                                       continue;
+                               }
+                               list += 2;
+                               desc_val = pgm_read_word(list);
+                               if (desc_val != wIndex) {
+                                       list += sizeof(struct descriptor_list_struct)-2;
+                                       continue;
+                               }
+                               list += 2;
+                               desc_addr = (const uint8_t *)pgm_read_word(list);
+                               list += 2;
+                               desc_length = pgm_read_byte(list);
+                               break;
+                       }
+                       len = (wLength < 256) ? wLength : 255;
+                       if (len > desc_length) len = desc_length;
+                       do {
+                               // wait for host ready for IN packet
+                               do {
+                                       i = UEINTX;
+                               } while (!(i & ((1<<TXINI)|(1<<RXOUTI))));
+                               if (i & (1<<RXOUTI))
+                               {
+                                       return; // abort
+                               }
+                               // send IN packet
+                               n = len < ENDPOINT0_SIZE ? len : ENDPOINT0_SIZE;
+                               for (i = n; i; i--) {
+                                       UEDATX = pgm_read_byte(desc_addr++);
+                               }
+                               len -= n;
+                               usb_send_in();
+                       } while (len || n == ENDPOINT0_SIZE);
+                       return;
+               }
+               if (bRequest == SET_ADDRESS) {
+                       usb_send_in();
+                       usb_wait_in_ready();
+                       UDADDR = wValue | (1<<ADDEN);
+                       return;
+               }
+               if (bRequest == SET_CONFIGURATION && bmRequestType == 0) {
+                       usb_configuration = wValue;
+                       cdc_line_rtsdtr = 0;
+                       transmit_flush_timer = 0;
+                       usb_send_in();
+                       cfg = endpoint_config_table;
+                       for (i=1; i<5; i++) {
+                               UENUM = i;
+                               en = pgm_read_byte(cfg++);
+                               UECONX = en;
+                               if (en) {
+                                       UECFG0X = pgm_read_byte(cfg++);
+                                       UECFG1X = pgm_read_byte(cfg++);
+                               }
+                       }
+                               UERST = 0x1E;
+                               UERST = 0;
+                       return;
+               }
+               if (bRequest == GET_CONFIGURATION && bmRequestType == 0x80) {
+                       usb_wait_in_ready();
+                       UEDATX = usb_configuration;
+                       usb_send_in();
+                       return;
+               }
+               if (bRequest == CDC_GET_LINE_CODING && bmRequestType == 0xA1) {
+                       usb_wait_in_ready();
+                       p = cdc_line_coding;
+                       for (i=0; i<7; i++) {
+                               UEDATX = *p++;
+                       }
+                       usb_send_in();
+                       return;
+               }
+               if (bRequest == CDC_SET_LINE_CODING && bmRequestType == 0x21) {
+                       usb_wait_receive_out();
+                       p = cdc_line_coding;
+                       for (i=0; i<7; i++) {
+                               *p++ = UEDATX;
+                       }
+                       usb_ack_out();
+                       usb_send_in();
+                       return;
+               }
+               if (bRequest == CDC_SET_CONTROL_LINE_STATE && bmRequestType == 0x21) {
+                       cdc_line_rtsdtr = wValue;
+                       usb_wait_in_ready();
+                       usb_send_in();
+                       return;
+               }
+               if (bRequest == GET_STATUS) {
+                       usb_wait_in_ready();
+                       i = 0;
+                       #ifdef SUPPORT_ENDPOINT_HALT
+                       if (bmRequestType == 0x82) {
+                               UENUM = wIndex;
+                               if (UECONX & (1<<STALLRQ)) i = 1;
+                               UENUM = 0;
+                       }
+                       #endif
+                       UEDATX = i;
+                       UEDATX = 0;
+                       usb_send_in();
+                       return;
+               }
+               #ifdef SUPPORT_ENDPOINT_HALT
+               if ((bRequest == CLEAR_FEATURE || bRequest == SET_FEATURE)
+                 && bmRequestType == 0x02 && wValue == 0) {
+                       i = wIndex & 0x7F;
+                       if (i >= 1 && i <= MAX_ENDPOINT) {
+                               usb_send_in();
+                               UENUM = i;
+                               if (bRequest == SET_FEATURE) {
+                                       UECONX = (1<<STALLRQ)|(1<<EPEN);
+                               } else {
+                                       UECONX = (1<<STALLRQC)|(1<<RSTDT)|(1<<EPEN);
+                                       UERST = (1 << i);
+                                       UERST = 0;
+                               }
+                               return;
+                       }
+               }
+               #endif
+       }
+       UECONX = (1<<STALLRQ) | (1<<EPEN);      // stall
+}
+
+
+#define CPU_PRESCALE(n) (CLKPR = 0x80, CLKPR = (n))
+
+#if 0
+#include <stdio.h>
+static int dw_putchar(char __c, FILE *__stream) { DWDR = __c;(void)__stream; return __c;}
+FILE dwout = FDEV_SETUP_STREAM(dw_putchar, NULL, _FDEV_SETUP_WRITE);
+stdout=&dwout;
+#endif
+
+// Very simple character echo test
+int main(void)
+{
+       CPU_PRESCALE(0);
+       usb_init();
+       while(usb_configured()==0);
+       while (1) {
+               int n = usb_serial_getchar();
+               if (n >= 0) usb_serial_putchar(n);
+       }
+}
diff --git a/examples/board_usb/at90usb162_cdc_loopback.h b/examples/board_usb/at90usb162_cdc_loopback.h
new file mode 100644 (file)
index 0000000..2d83706
--- /dev/null
@@ -0,0 +1,125 @@
+/* vim: set sts=4:sw=4:ts=4:noexpandtab */
+#ifndef usb_serial_h__
+#define usb_serial_h__
+
+#include <stdint.h>
+
+// setup
+void usb_init(void);                   // initialize everything
+uint8_t usb_configured(void);          // is the USB port configured
+
+// receiving data
+int16_t usb_serial_getchar(void);      // receive a character (-1 if timeout/error)
+uint8_t usb_serial_available(void);    // number of bytes in receive buffer
+void usb_serial_flush_input(void);     // discard any buffered input
+
+// transmitting data
+int8_t usb_serial_putchar(uint8_t c);  // transmit a character
+int8_t usb_serial_putchar_nowait(uint8_t c);  // transmit a character, do not wait
+int8_t usb_serial_write(const uint8_t *buffer, uint16_t size); // transmit a buffer
+void usb_serial_flush_output(void);    // immediately transmit any buffered output
+
+// serial parameters
+uint32_t usb_serial_get_baud(void);    // get the baud rate
+uint8_t usb_serial_get_stopbits(void); // get the number of stop bits
+uint8_t usb_serial_get_paritytype(void);// get the parity type
+uint8_t usb_serial_get_numbits(void);  // get the number of data bits
+uint8_t usb_serial_get_control(void);  // get the RTS and DTR signal state
+int8_t usb_serial_set_control(uint8_t signals); // set DSR, DCD, RI, etc
+
+// constants corresponding to the various serial parameters
+#define USB_SERIAL_DTR                 0x01
+#define USB_SERIAL_RTS                 0x02
+#define USB_SERIAL_1_STOP              0
+#define USB_SERIAL_1_5_STOP            1
+#define USB_SERIAL_2_STOP              2
+#define USB_SERIAL_PARITY_NONE         0
+#define USB_SERIAL_PARITY_ODD          1
+#define USB_SERIAL_PARITY_EVEN         2
+#define USB_SERIAL_PARITY_MARK         3
+#define USB_SERIAL_PARITY_SPACE                4
+#define USB_SERIAL_DCD                 0x01
+#define USB_SERIAL_DSR                 0x02
+#define USB_SERIAL_BREAK               0x04
+#define USB_SERIAL_RI                  0x08
+#define USB_SERIAL_FRAME_ERR           0x10
+#define USB_SERIAL_PARITY_ERR          0x20
+#define USB_SERIAL_OVERRUN_ERR         0x40
+
+// This file does not include the HID debug functions, so these empty
+// macros replace them with nothing, so users can compile code that
+// has calls to these functions.
+#define usb_debug_putchar(c)
+#define usb_debug_flush_output()
+
+
+
+// Everything below this point is only intended for usb_serial.c
+#ifdef USB_SERIAL_PRIVATE_INCLUDE
+#include <avr/io.h>
+#include <avr/pgmspace.h>
+#include <avr/interrupt.h>
+
+#define EP_TYPE_CONTROL                        0x00
+#define EP_TYPE_BULK_IN                        0x81
+#define EP_TYPE_BULK_OUT               0x80
+#define EP_TYPE_INTERRUPT_IN           0xC1
+#define EP_TYPE_INTERRUPT_OUT          0xC0
+#define EP_TYPE_ISOCHRONOUS_IN         0x41
+#define EP_TYPE_ISOCHRONOUS_OUT                0x40
+#define EP_SINGLE_BUFFER               0x02
+#define EP_DOUBLE_BUFFER               0x06
+#define EP_SIZE(s)     ((s) == 64 ? 0x30 :     \
+                       ((s) == 32 ? 0x20 :     \
+                       ((s) == 16 ? 0x10 :     \
+                                    0x00)))
+
+#define MAX_ENDPOINT           4
+
+#define LSB(n) (n & 255)
+#define MSB(n) ((n >> 8) & 255)
+
+#if defined(__AVR_AT90USB162__)
+#define HW_CONFIG()
+#define PLL_CONFIG() (PLLCSR = ((1<<PLLE)|(1<<PLLP0)))
+#define USB_CONFIG() (USBCON = (1<<USBE))
+#define USB_FREEZE() (USBCON = ((1<<USBE)|(1<<FRZCLK)))
+#elif defined(__AVR_ATmega32U4__)
+#define HW_CONFIG() (UHWCON = 0x01)
+#define PLL_CONFIG() (PLLCSR = 0x12)
+#define USB_CONFIG() (USBCON = ((1<<USBE)|(1<<OTGPADE)))
+#define USB_FREEZE() (USBCON = ((1<<USBE)|(1<<FRZCLK)))
+#elif defined(__AVR_AT90USB646__)
+#define HW_CONFIG() (UHWCON = 0x81)
+#define PLL_CONFIG() (PLLCSR = 0x1A)
+#define USB_CONFIG() (USBCON = ((1<<USBE)|(1<<OTGPADE)))
+#define USB_FREEZE() (USBCON = ((1<<USBE)|(1<<FRZCLK)))
+#elif defined(__AVR_AT90USB1286__)
+#define HW_CONFIG() (UHWCON = 0x81)
+#define PLL_CONFIG() (PLLCSR = 0x16)
+#define USB_CONFIG() (USBCON = ((1<<USBE)|(1<<OTGPADE)))
+#define USB_FREEZE() (USBCON = ((1<<USBE)|(1<<FRZCLK)))
+#endif
+
+// standard control endpoint request types
+#define GET_STATUS                     0
+#define CLEAR_FEATURE                  1
+#define SET_FEATURE                    3
+#define SET_ADDRESS                    5
+#define GET_DESCRIPTOR                 6
+#define GET_CONFIGURATION              8
+#define SET_CONFIGURATION              9
+#define GET_INTERFACE                  10
+#define SET_INTERFACE                  11
+// HID (human interface device)
+#define HID_GET_REPORT                 1
+#define HID_GET_PROTOCOL               3
+#define HID_SET_REPORT                 9
+#define HID_SET_IDLE                   10
+#define HID_SET_PROTOCOL               11
+// CDC (communication class device)
+#define CDC_SET_LINE_CODING            0x20
+#define CDC_GET_LINE_CODING            0x21
+#define CDC_SET_CONTROL_LINE_STATE     0x22
+#endif
+#endif
diff --git a/examples/board_usb/simusb.c b/examples/board_usb/simusb.c
new file mode 100644 (file)
index 0000000..e779890
--- /dev/null
@@ -0,0 +1,139 @@
+/* vim: set sts=4:sw=4:ts=4:noexpandtab
+       simusb.c
+
+       Copyright 2012 Torbjorn Tyridal <ttyridal@gmail.com>
+
+       This file is part of simavr.
+
+       simavr is free software: you can redistribute it and/or modify
+       it under the terms of the GNU General Public License as published by
+       the Free Software Foundation, either version 3 of the License, or
+       (at your option) any later version.
+
+       simavr is distributed in the hope that it will be useful,
+       but WITHOUT ANY WARRANTY; without even the implied warranty of
+       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+       GNU General Public License for more details.
+
+       You should have received a copy of the GNU General Public License
+       along with simavr.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <sys/mman.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <libgen.h>
+
+#include <pthread.h>
+
+#include "sim_avr.h"
+#include "avr_ioport.h"
+#include "sim_elf.h"
+#include "sim_hex.h"
+#include "sim_gdb.h"
+#include "vhci_usb.h"
+#include "sim_vcd_file.h"
+
+struct vhci_usb_t vhci_usb;
+avr_t * avr = NULL;
+avr_vcd_t vcd_file;
+
+
+
+char avr_flash_path[1024];
+int avr_flash_fd = 0;
+
+// avr special flash initalization
+// here: open and map a file to enable a persistent storage for the flash memory
+void avr_special_init( avr_t* avr)
+{
+       //puts(" --=== INIT CALLED ===--");
+       // release flash memory if allocated
+       if(avr->flash) free(avr->flash);
+       // open the file
+       avr_flash_fd = open(avr_flash_path, O_RDWR|O_CREAT, 0644);
+       if (avr_flash_fd < 0) {
+               perror(avr_flash_path);
+               exit(1);
+       }
+       // resize and map the file the file
+       (void)ftruncate(avr_flash_fd, avr->flashend + 1);
+       avr->flash = (uint8_t*)mmap(NULL, avr->flashend + 1, // 32k is multiple of 4096
+                                                       PROT_READ|PROT_WRITE, MAP_SHARED, avr_flash_fd, 0);
+       if (!avr->flash) {
+               fprintf(stderr, "unable to map memory\n");
+               perror(avr_flash_path);
+               exit(1);
+       }
+}
+
+// avr special flash deinitalization
+// here: cleanup the persistent storage
+void avr_special_deinit( avr_t* avr)
+{
+       //puts(" --=== DEINIT CALLED ===--");
+       // unmap and close the file
+       munmap( avr->flash, avr->flashend + 1);
+       close( avr_flash_fd);
+       // signal that cleanup is done
+       avr->flash = NULL;
+}
+
+int main(int argc, char *argv[])
+{
+       elf_firmware_t f;
+       const char * pwd = dirname(argv[0]);
+
+       avr = avr_make_mcu_by_name("at90usb162");
+       if (!avr) {
+               fprintf(stderr, "%s: Error creating the AVR core\n", argv[0]);
+               exit(1);
+       }
+       strcpy(avr_flash_path,  "simusb_flash.bin");
+       // register our own functions
+       avr->special_init = avr_special_init;
+       avr->special_deinit = avr_special_deinit;
+       //avr->reset = NULL;
+       avr_init(avr);
+       avr->frequency = 8000000;
+
+       // this trick creates a file that contains /and keep/ the flash
+       // in the same state as it was before. This allow the bootloader
+       // app to be kept, and re-run if the bootloader doesn't get a
+       // new one
+       {
+               char path[1024];
+               uint32_t base, size;
+               snprintf(path, sizeof(path), "%s/../%s", pwd, "at90usb162_cdc_loopback.hex");
+
+               uint8_t * boot = read_ihex_file(path, &size, &base);
+               if (!boot) {
+                       fprintf(stderr, "%s: Unable to load %s\n", argv[0], path);
+                       exit(1);
+               }
+               printf("Booloader %04x: %d\n", base, size);
+               memcpy(avr->flash + base, boot, size);
+               free(boot);
+               avr->pc = base;
+               avr->codeend = avr->flashend;
+       }
+
+       // even if not setup at startup, activate gdb if crashing
+       avr->gdb_port = 1234;
+       if (0) {
+               //avr->state = cpu_Stopped;
+               avr_gdb_init(avr);
+       }
+
+       vhci_usb_init(avr, &vhci_usb);
+       vhci_usb_connect(&vhci_usb, '0');
+
+
+       while (1) {
+               avr_run(avr);
+       }
+}