X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=simavr%2Fsim%2Favr_uart.c;h=149d8b9e56fd4b38ac1c02407c3e2391036ede0e;hb=fb5a31d1e731a1d3f1993063496277c979ce356e;hp=3193575b88f7dc908a68b39967541d4f61587b4b;hpb=2c3afb1f55a6f6b5553070fb09e95ec8add12c3d;p=simavr

diff --git a/simavr/sim/avr_uart.c b/simavr/sim/avr_uart.c
index 3193575..149d8b9 100644
--- a/simavr/sim/avr_uart.c
+++ b/simavr/sim/avr_uart.c
@@ -23,18 +23,33 @@
 	along with simavr.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#ifdef NO_COLOR
+	#define FONT_GREEN		
+	#define FONT_DEFAULT	
+#else
+	#define FONT_GREEN		"\e[32m"
+	#define FONT_DEFAULT	"\e[0m"
+#endif
+
 #include <stdio.h>
 #include <unistd.h>
+#include <stdint.h>
+#include <stdlib.h>
 #include "avr_uart.h"
 #include "sim_hex.h"
 
-DEFINE_FIFO(uint8_t, uart_fifo, 64);
+//#define TRACE(_w) _w
+#ifndef TRACE
+#define TRACE(_w)
+#endif
+
+DEFINE_FIFO(uint8_t, uart_fifo);
 
 static avr_cycle_count_t avr_uart_txc_raise(struct avr_t * avr, avr_cycle_count_t when, void * param)
 {
 	avr_uart_t * p = (avr_uart_t *)param;
 	if (avr_regbit_get(avr, p->txen)) {
-		// if the interrupts are not used, still raised the UDRE and TXC flag
+		// if the interrupts are not used, still raise the UDRE and TXC flag
 		avr_raise_interrupt(avr, &p->udrc);
 		avr_raise_interrupt(avr, &p->txc);
 	}
@@ -58,7 +73,7 @@ static uint8_t avr_uart_rxc_read(struct avr_t * avr, avr_io_addr_t addr, void *
 	//
 	// if RX is enabled, and there is nothing to read, and
 	// the AVR core is reading this register, it's probably
-	// to pool the RXC TXC flag and spinloop
+	// to poll the RXC TXC flag and spinloop
 	// so here we introduce a usleep to make it a bit lighter
 	// on CPU and let data arrive
 	//
@@ -71,8 +86,10 @@ static uint8_t avr_uart_rxc_read(struct avr_t * avr, avr_io_addr_t addr, void *
 			usleep(1);
 	}
 	// if reception is idle and the fifo is empty, tell whomever there is room
-	if (avr_regbit_get(avr, p->rxen) && uart_fifo_isempty(&p->input))
+	if (avr_regbit_get(avr, p->rxen) && uart_fifo_isempty(&p->input)) {
+		avr_raise_irq(p->io.irq + UART_IRQ_OUT_XOFF, 0);
 		avr_raise_irq(p->io.irq + UART_IRQ_OUT_XON, 1);
+	}
 
 	return v;
 }
@@ -81,7 +98,7 @@ static uint8_t avr_uart_read(struct avr_t * avr, avr_io_addr_t addr, void * para
 {
 	avr_uart_t * p = (avr_uart_t *)param;
 
-	// clear the rxc bit in case the code is using pooling
+	// clear the rxc bit in case the code is using polling
 	avr_regbit_clear(avr, p->rxc.raised);
 
 	if (!avr_regbit_get(avr, p->rxen)) {
@@ -92,13 +109,14 @@ static uint8_t avr_uart_read(struct avr_t * avr, avr_io_addr_t addr, void * para
 	}
 	uint8_t v = uart_fifo_read(&p->input);
 
-	//printf("UART read %02x %s\n", v, uart_fifo_isempty(&p->input) ? "EMPTY!" : "");
+//	TRACE(printf("UART read %02x %s\n", v, uart_fifo_isempty(&p->input) ? "EMPTY!" : "");)
 	avr->data[addr] = v;
 	// made to trigger potential watchpoints
 	v = avr_core_watch_read(avr, addr);
 
+	// trigger timer if more characters are pending
 	if (!uart_fifo_isempty(&p->input))
-		avr_cycle_timer_register_usec(avr, 100, avr_uart_rxc_raise, p); // should be uart speed dependent
+		avr_cycle_timer_register_usec(avr, p->usec_per_byte, avr_uart_rxc_raise, p);
 
 	return v;
 }
@@ -113,7 +131,17 @@ static void avr_uart_baud_write(struct avr_t * avr, avr_io_addr_t addr, uint8_t
 		baud /= 8;
 	else
 		baud /= 16;
-	printf("UART-%c configured to %04x = %d baud\n", p->name, val, baud);
+
+	const int databits[] = { 5,6,7,8,  /* 'reserved', assume 8 */8,8,8, 9 };
+	int db = databits[avr_regbit_get(avr, p->ucsz) | (avr_regbit_get(avr, p->ucsz2) << 2)];
+	int sb = 1 + avr_regbit_get(avr, p->usbs);
+	int word_size = 1 /* start */ + db /* data bits */ + 1 /* parity */ + sb /* stops */;
+
+	AVR_LOG(avr, LOG_TRACE, "UART: %c configured to %04x = %d bps (x%d), %d data %d stop\n",
+			p->name, val, baud, avr_regbit_get(avr, p->u2x)?2:1, db, sb);
+	// TODO: Use the divider value and calculate the straight number of cycles
+	p->usec_per_byte = 1000000 / (baud / word_size);
+	AVR_LOG(avr, LOG_TRACE, "UART: Roughly %d usec per bytes\n", (int)p->usec_per_byte);
 }
 
 static void avr_uart_write(struct avr_t * avr, avr_io_addr_t addr, uint8_t v, void * param)
@@ -123,50 +151,52 @@ static void avr_uart_write(struct avr_t * avr, avr_io_addr_t addr, uint8_t v, vo
 	if (addr == p->r_udr) {
 		avr_core_watch_write(avr, addr, v);
 
-		avr_regbit_clear(avr, p->udrc.raised);
-		avr_cycle_timer_register_usec(avr, 100, avr_uart_txc_raise, p); // should be uart speed dependent
+		if ( p->udrc.vector)
+			avr_regbit_clear(avr, p->udrc.raised);
+		avr_cycle_timer_register_usec(avr,
+				p->usec_per_byte, avr_uart_txc_raise, p); // should be uart speed dependent
 
 		if (p->flags & AVR_UART_FLAG_STDIO) {
-			static char buf[128];
-			static int l = 0;
-			buf[l++] = v < ' ' ? '.' : v;
-			buf[l] = 0;
-			if (v == '\n' || l == 127) {
-				l = 0;
-				printf("\e[32m%s\e[0m\n", buf);
+			const int maxsize = 256;
+			if (!p->stdio_out)
+				p->stdio_out = malloc(maxsize);
+			p->stdio_out[p->stdio_len++] = v < ' ' ? '.' : v;
+			p->stdio_out[p->stdio_len] = 0;
+			if (v == '\n' || p->stdio_len == maxsize) {
+				p->stdio_len = 0;
+				AVR_LOG(avr, LOG_TRACE, FONT_GREEN "%s\n" FONT_DEFAULT, p->stdio_out);
 			}
 		}
-	//	printf("UDR%c(%02x) = %02x\n", p->name, addr, v);
-		// tell other modules we are "outputing" a byte
+		TRACE(printf("UDR%c(%02x) = %02x\n", p->name, addr, v);)
+		// tell other modules we are "outputting" a byte
 		if (avr_regbit_get(avr, p->txen))
 			avr_raise_irq(p->io.irq + UART_IRQ_OUTPUT, v);
 	}
-	if (addr == p->udrc.enable.reg) {
+	if (p->udrc.vector && addr == p->udrc.enable.reg) {
 		/*
-		 * If enabling the UDRC interupt, raise it immediately if FIFO is empty
+		 * If enabling the UDRC interrupt, raise it immediately if FIFO is empty
 		 */
 		uint8_t udrce = avr_regbit_get(avr, p->udrc.enable);
 		avr_core_watch_write(avr, addr, v);
 		uint8_t nudrce = avr_regbit_get(avr, p->udrc.enable);
 		if (!udrce && nudrce) {
-			// if the FIDO is not empty (clear timer is flying) we dont
-			// need to raise the interupt, it will happend when the timer
+			// if the FIDO is not empty (clear timer is flying) we don't
+			// need to raise the interrupt, it will happen when the timer
 			// is fired.
 			if (avr_cycle_timer_status(avr, avr_uart_txc_raise, p) == 0)
 				avr_raise_interrupt(avr, &p->udrc);
 		}
 	}
-	if (addr == p->udrc.raised.reg) {
+	if (p->udrc.vector && addr == p->udrc.raised.reg) {
 		// get the bits before the write
-		uint8_t udre = avr_regbit_get(avr, p->udrc.raised);
+		//uint8_t udre = avr_regbit_get(avr, p->udrc.raised);
 		uint8_t txc = avr_regbit_get(avr, p->txc.raised);
 
-		// no need to write this value in here, only the
-		// interupt flags needs clearing!
-		// avr_core_watch_write(avr, addr, v);
+                // required for u2x (double uart transmission speed)
+		avr_core_watch_write(avr, addr, v);
 
-		avr_clear_interupt_if(avr, &p->udrc, udre);
-		avr_clear_interupt_if(avr, &p->txc, txc);
+		//avr_clear_interrupt_if(avr, &p->udrc, udre);
+		avr_clear_interrupt_if(avr, &p->txc, txc);
 	}
 }
 
@@ -175,15 +205,15 @@ static void avr_uart_irq_input(struct avr_irq_t * irq, uint32_t value, void * pa
 	avr_uart_t * p = (avr_uart_t *)param;
 	avr_t * avr = p->io.avr;
 
-	// check to see fi receiver is enabled
+	// check to see if receiver is enabled
 	if (!avr_regbit_get(avr, p->rxen))
 		return;
 
 	if (uart_fifo_isempty(&p->input))
-		avr_cycle_timer_register_usec(avr, 100, avr_uart_rxc_raise, p); // should be uart speed dependent
+		avr_cycle_timer_register_usec(avr, p->usec_per_byte, avr_uart_rxc_raise, p); // should be uart speed dependent
 	uart_fifo_write(&p->input, value); // add to fifo
 
-//	printf("UART IRQ in %02x (%d/%d) %s\n", value, p->input.read, p->input.write, uart_fifo_isfull(&p->input) ? "FULL!!" : "");
+	TRACE(printf("UART IRQ in %02x (%d/%d) %s\n", value, p->input.read, p->input.write, uart_fifo_isfull(&p->input) ? "FULL!!" : "");)
 
 	if (uart_fifo_isfull(&p->input))
 		avr_raise_irq(p->io.irq + UART_IRQ_OUT_XOFF, 1);
@@ -194,15 +224,19 @@ void avr_uart_reset(struct avr_io_t *io)
 {
 	avr_uart_t * p = (avr_uart_t *)io;
 	avr_t * avr = p->io.avr;
-	avr_regbit_set(avr, p->udrc.raised);
+	if (p->udrc.vector)
+		avr_regbit_set(avr, p->udrc.raised);
 	avr_irq_register_notify(p->io.irq + UART_IRQ_INPUT, avr_uart_irq_input, p);
 	avr_cycle_timer_cancel(avr, avr_uart_rxc_raise, p);
 	avr_cycle_timer_cancel(avr, avr_uart_txc_raise, p);
 	uart_fifo_reset(&p->input);
 
-	// DEBUG allow printf without fidding with enabling the uart
-	avr_regbit_set(avr, p->txen);
+        avr_regbit_set(avr, p->ucsz);
+        avr_regbit_clear(avr, p->ucsz2);
 
+	// DEBUG allow printf without fiddling with enabling the uart
+	avr_regbit_set(avr, p->txen);
+	p->usec_per_byte = 100;
 }
 
 static int avr_uart_ioctl(struct avr_io_t * port, uint32_t ctl, void * io_param)
@@ -254,14 +288,19 @@ void avr_uart_init(avr_t * avr, avr_uart_t * p)
 
 	// allocate this module's IRQ
 	avr_io_setirqs(&p->io, AVR_IOCTL_UART_GETIRQ(p->name), UART_IRQ_COUNT, NULL);
+	// Only call callbacks when the value change...
+	p->io.irq[UART_IRQ_OUT_XOFF].flags |= IRQ_FLAG_FILTERED;
 
 	avr_register_io_write(avr, p->r_udr, avr_uart_write, p);
-	avr_register_io_write(avr, p->udrc.enable.reg, avr_uart_write, p);
 	avr_register_io_read(avr, p->r_udr, avr_uart_read, p);
 	// monitor code that reads the rxc flag, and delay it a bit
 	avr_register_io_read(avr, p->rxc.raised.reg, avr_uart_rxc_read, p);
 
-	avr_register_io_write(avr, p->r_ucsra, avr_uart_write, p);
-	avr_register_io_write(avr, p->r_ubrrl, avr_uart_baud_write, p);
+	if (p->udrc.vector)
+		avr_register_io_write(avr, p->udrc.enable.reg, avr_uart_write, p);
+	if (p->r_ucsra)
+		avr_register_io_write(avr, p->r_ucsra, avr_uart_write, p);
+	if (p->r_ubrrl)
+		avr_register_io_write(avr, p->r_ubrrl, avr_uart_baud_write, p);
 }