From: travisutk <travisutk@12e2690d-a6be-4b82-a7b7-67c4a43b65c8>
Date: Mon, 7 May 2012 13:41:18 +0000 (+0000)
Subject: Struggling with STM32 USART.
X-Git-Url: http://git.rot13.org/?p=goodfet;a=commitdiff_plain;h=e686a9e7cc4fcd2cd5d269b41500f7c421b10b55

Struggling with STM32 USART.

git-svn-id: https://svn.code.sf.net/p/goodfet/code/trunk@1162 12e2690d-a6be-4b82-a7b7-67c4a43b65c8
---

diff --git a/firmware/lib/stm32f407.c b/firmware/lib/stm32f407.c
index 167d05a..c75e631 100644
--- a/firmware/lib/stm32f407.c
+++ b/firmware/lib/stm32f407.c
@@ -9,9 +9,8 @@
 //#include "stm322xg_eval.h"
 #include <stm32f4xx_gpio.h>
 #include <stm32f4xx_rcc.h>
-#include <stm32f4xx_rcc.h>
-//#include "stm32f4_discovery.h"
-
+#include <stm32f4xx_usart.h>
+#include "stm32f4_discovery.h"
 
 void ioinit(){
   GPIO_InitTypeDef  GPIO_InitStructure;
@@ -23,37 +22,129 @@ void ioinit(){
   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12 | GPIO_Pin_13| GPIO_Pin_14| GPIO_Pin_15;
   GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
   GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
-  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
+  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
   GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
   GPIO_Init(GPIOD, &GPIO_InitStructure);
 }
 
-
+void stmdelay(){
+  //IO so it doesn't get swapped out.
+  __IO uint32_t count=   0x1000;   // >1kbit/s
+  //__IO uint32_t count= 0x100000; // 5 bits per second, for testing
+  while(count--);
+}
 void ledon(){
-  //GPIOG->BSRRL=GPIO_Pin_14;
-  GPIO_ResetBits(GPIOD, GPIO_Pin_14);
+  GPIO_SetBits(GPIOD, GPIO_Pin_14);
 }
 void ledoff(){
-  //GPIOG->BSRRH=GPIO_Pin_14;
-  GPIO_SetBits(GPIOD, GPIO_Pin_14);
+  GPIO_ResetBits(GPIOD, GPIO_Pin_14);
+}
+void clkon(){
+  GPIO_SetBits(GPIOD, GPIO_Pin_12);
+}
+void clkoff(){
+  GPIO_ResetBits(GPIOD, GPIO_Pin_12);
 }
 
+void spibit(int one){
+  if(one) ledon();
+  else    ledoff();
+  clkon();
+  stmdelay();
+  clkoff();
+  stmdelay();
+}
+
+void spiword(uint32_t word){
+  int i=32;
+  while(i--){
+    //morsebit(word&1);
+    //manchesterbit(word&1);
+    spibit(word&1);
+    word=(word>>1);
+  }
+}
+void spibyte(uint8_t word){
+  int i=8;
+  while(i--){
+    //morsebit(word&1);
+    //manchesterbit(word&1);
+    spibit(word&1);
+    word=(word>>1);
+  }
+}
+
+
 
 //! Count the length of a string.
 uint32_t strlen(const char *s){
-  return 0;
+  int i=0;
+  while(s[i++]);
+  return i-1;
+}
+
+
+//! Initialize the USART
+void usartinit(){
+  USART_InitTypeDef USART_InitStructure;
+  GPIO_InitTypeDef GPIO_InitStructure;
+  USART_ClockInitTypeDef USART_ClockInitStruct;
+  
+  /* Enable GPIOA and USART1 clock */
+  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
+  
+  //USART1 and USART6, other in APB1
+  RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
+  
+  RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);
+  /* A 9 to USART1_Tx
+   * A10 to USART1_Rx
+   * A11 to USART1_CTS
+   * A12 to USART1_RTS 
+   */
+  GPIO_PinAFConfig(GPIOA, GPIO_PinSource9, GPIO_AF_USART1);
+  GPIO_PinAFConfig(GPIOA, GPIO_PinSource10, GPIO_AF_USART1);
+  GPIO_PinAFConfig(GPIOA, GPIO_PinSource11, GPIO_AF_USART1);
+  GPIO_PinAFConfig(GPIOA, GPIO_PinSource12, GPIO_AF_USART1);
+ 
+  /* Configure USART Tx and Rx as alternate function push-pull */
+  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
+  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
+  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
+  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
+  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_10 | GPIO_Pin_11 | GPIO_Pin_12;
+  GPIO_Init(GPIOA, &GPIO_InitStructure);
+  
+  
+  USART_StructInit(&USART_InitStructure);
+  USART_InitStructure.USART_BaudRate = 9600;
+  USART_InitStructure.USART_WordLength = USART_WordLength_8b;
+  USART_InitStructure.USART_StopBits = USART_StopBits_1;
+  USART_InitStructure.USART_Parity = USART_Parity_No;
+  USART_InitStructure.USART_HardwareFlowControl =  USART_HardwareFlowControl_None;
+  USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
+  USART_Init(USART1, &USART_InitStructure);
+  
+  
+  USART_ClockStructInit(&USART_ClockInitStruct);
+  USART_ClockInit(USART1,&USART_ClockInitStruct);
+  
+  USART_Cmd(USART1, ENABLE);
 }
 
+
 //! Initialize the STM32F4xx ports and USB.
 void stm32f4xx_init(){
-  SystemInit();
+  int i=20;
+  
+  //SystemInit();
+  usartinit();
   ioinit();
-  while(1){
-    ledon();
-    delay(0x1000);
-    ledoff();
-    delay(0x1000);
-  }
+  
+  ledoff();
+  clkoff();
+  
+  return;
 }
 
 //! Receive a byte.
@@ -66,9 +157,10 @@ unsigned char serial1_rx(){
 
 //! Transmit a byte.
 void serial0_tx(unsigned char x){
-}
-//! Transmit a byte.
-void serial_tx_old(unsigned char x){
+  USART_SendData(USART1, (uint16_t) x);
+  //while(USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
+  
+  spibyte(x);
 }
 
 //! Transmit a byte on the second UART.
@@ -95,8 +187,6 @@ int main(void);
 //From min.s
 void Reset_Handler(void);
 
-
-
 // Define the vector table
 unsigned int * myvectors[50] 
    __attribute__ ((section("vectors")))= {