Fixed delayMicroseconds, changed serial interface, added an (untested) runtime check for pwm/serial collision, moved more headers around.

git-svn-id: https://leaflabs.googlecode.com/svn/trunk/library@79 749a229e-a60e-11de-b98f-4500b42dc123

12 files changed, 82 insertions, 141 deletions

diff --git a/README.txt b/README.txt
index 802aa24..17f813e 100644
--- a/README.txt
+++ b/README.txt
@@ -7,22 +7,10 @@
  * D15 is mapped to pin number 38. This is to retain compatiblity with the
  * Arduino API, where digitalWrite() on pins 14-19 map to analog A0-A5
  *
- * Fix serial/timer 
- * Add external itnerrupts
- * Redo serial api
- *
- * Order some shields
- * buy some toner
- * LARW BOOK
- *
- *
- * wtf is smba/smbal?
- * serial.print
- *
- * 5v tolerance
  *
  * TODO:
  * Using OSC32_IN/OSC32_OUT pins as GPIO ports PC14/PC15 152/995
+ * Runtime check for AF collisions on pins (eg serial and pwm).
  * */
 
 /* 51 GPIOs in general
diff --git a/src/lib/gpio.c b/src/lib/gpio.c
index 1e42d4d..f03c4fa 100644
--- a/src/lib/gpio.c
+++ b/src/lib/gpio.c
@@ -23,10 +23,6 @@
  *  @brief GPIO initialization routine
  */
 
-#ifndef _GPIO_H_
-#define _GPIO_H_
-
-#endif
 #include "libmaple.h"
 #include "stm32f10x_rcc.h"
 #include "gpio.h"
@@ -36,11 +32,11 @@ void gpio_init(void) {
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA |
                           RCC_APB2Periph_GPIOB |
                           RCC_APB2Periph_GPIOC |
-                          RCC_APB2Periph_AFIO, 
+                          RCC_APB2Periph_AFIO,
                           ENABLE);
 }
 
-void gpio_set_mode(GPIO_Port* port, uint8_t gpio_pin, uint8_t mode) {
+void gpio_set_mode(GPIO_Port* port, uint8 gpio_pin, uint8 mode) {
     uint32_t tmp;
     uint32_t shift = POS(gpio_pin % 8);
     GPIOReg CR;
diff --git a/src/lib/gpio.h b/src/lib/gpio.h
index bc9bdde..5e7cf29 100644
--- a/src/lib/gpio.h
+++ b/src/lib/gpio.h
@@ -58,25 +58,17 @@
 #define GPIO_MODE_INPUT_PD          (0x02 << 2)
 #define GPIO_MODE_INPUT_PU          (0x02 << 2)
 
-//#define INPUT_ANALOG                GPIO_MODE_INPUT_ANALOG
-//#define INPUT_DIGITAL               GPIO_MODE_INPUT_FLOATING
-//#define INPUT_FLOATING              GPIO_MODE_INPUT_FLOATING
-//#define INPUT_PULLDOWN              GPIO_MODE_INPUT_PD
-//#define INPUT_PULLUP                GPIO_MODE_INPUT_PU
-//#define INPUT                       GPIO_MODE_INPUT_FLOATING
-//#define OUTPUT                      GPIO_MODE_OUTPUT_PP
-
 typedef struct {
-    volatile uint32_t CRL;      // Port configuration register low
-    volatile uint32_t CRH;      // Port configuration register high
-    volatile uint32_t IDR;      // Port input data register
-    volatile uint32_t ODR;      // Port output data register
-    volatile uint32_t BSRR;     // Port bit set/reset register
-    volatile uint32_t BRR;      // Port bit reset register
-    volatile uint32_t LCKR;     // Port configuration lock register
+    volatile uint32 CRL;      // Port configuration register low
+    volatile uint32 CRH;      // Port configuration register high
+    volatile uint32 IDR;      // Port input data register
+    volatile uint32 ODR;      // Port output data register
+    volatile uint32 BSRR;     // Port bit set/reset register
+    volatile uint32 BRR;      // Port bit reset register
+    volatile uint32 LCKR;     // Port configuration lock register
 } GPIO_Port;
 
-typedef volatile uint32_t* GPIOReg;
+typedef volatile uint32* GPIOReg;
 
 #define POS_MASK(shift) (~(0xF << shift))
 #define POS(val)        (val << 2)
@@ -86,9 +78,9 @@ extern "C"{
 #endif
 
 void gpio_init(void);
-void gpio_set_mode(GPIO_Port* port, uint8_t gpio_pin, uint8_t mode);
+void gpio_set_mode(GPIO_Port* port, uint8 gpio_pin, uint8 mode);
 
-static inline void gpio_write_bit(GPIO_Port *port, uint8_t gpio_pin, uint8_t val) {
+static inline void gpio_write_bit(GPIO_Port *port, uint8 gpio_pin, uint8 val) {
     if (val){
         port->BSRR = BIT(gpio_pin);
     } else {
diff --git a/src/lib/systick.h b/src/lib/systick.h
index 3d846ef..61789c4 100644
--- a/src/lib/systick.h
+++ b/src/lib/systick.h
@@ -51,7 +51,7 @@ extern "C"{
 void systick_init(void);
 
 static inline uint32_t systick_get_count(void) {
-    return (uint32_t)SYSTICK_CNT;
+    return (uint32_t)*(volatile uint32*)SYSTICK_CNT;
 }
 
 #ifdef __cplusplus
diff --git a/src/lib/timers.c b/src/lib/timers.c
index 2161d84..1e95f41 100644
--- a/src/lib/timers.c
+++ b/src/lib/timers.c
@@ -152,3 +152,40 @@ void timers_disable(void) {
         timer->CR1 = 0;
     }
 }
+
+void timers_disable_channel(uint8 timer_num, uint8 channel) {
+    Timer *timer;
+    switch (timer_num) {
+    case 1:
+        timer = (Timer*)TIMER1_BASE;
+        break;
+    case 2:
+        timer = (Timer*)TIMER2_BASE;
+        break;
+    case 3:
+        timer = (Timer*)TIMER3_BASE;
+        break;
+    case 4:
+        timer = (Timer*)TIMER4_BASE;
+        break;
+    default:
+        ASSERT(0);
+    }
+
+    switch (channel) {
+    case 1:
+        timer->CCER &= ~(0x1);
+        break;
+    case 2:
+        timer->CCER &= ~(0x10);
+        break;
+    case 3:
+        timer->CCER &= ~(0x100);
+        break;
+    case 4:
+        timer->CCER &= ~(0x1000);
+        break;
+    default:
+        ASSERT(0);
+    }
+}
diff --git a/src/lib/timers.h b/src/lib/timers.h
index 9147fd4..18b0afb 100644
--- a/src/lib/timers.h
+++ b/src/lib/timers.h
@@ -117,6 +117,7 @@ typedef volatile uint32_t* TimerCCR;
  * */
 void timer_init(uint8_t, uint16_t);
 void timers_disable(void);
+void timers_disable_channel(uint8, uint8);
 
 /* Turn on PWM with duty_cycle on the specified channel in timer.
  * This function takes in a pointer to the corresponding CCR
diff --git a/src/lib/usart.h b/src/lib/usart.h
index 4d0c586..b9efdd5 100644
--- a/src/lib/usart.h
+++ b/src/lib/usart.h
@@ -26,81 +26,6 @@
 #ifndef _USART_H_
 #define _USART_H_
 
-/* Transmit procedure:
- * 1.  Enable the USART by writing the UE bit in USART_CR1 register to 1.
- *
- * 2.  Program the M bit in USART_CR1 to define the word length.
- *
- * 3.  Program the number of stop bits in USART_CR2.
- *
- * 4.  Select DMA enable (DMAT) in USART_CR3 if Multi buffer Communication is
- *     to take place. Configure the DMA register as explained in multibuffer
- *     communication.
- *
- * 5.  Select the desired baud rate using the USART_BRR register.
- *
- * 6.  Set the TE bit in USART_CR1 to send an idle frame as first transmission.
- *
- * 7.  Write the data to send in the USART_DR register (this clears the TXE
- *     bit). Repeat this for each data to be transmitted in case of single buffer.
- *
- * 8.  After writing the last data into the USART_DR register, wait until TC=1.
- *     This indicates that the transmission of the last frame is complete. This is
- *     required for instance when the USART is disabled or enters the Halt mode to
- *     avoid corrupting the last transmission.
- *
- * Single byte communication
- * Clearing the TXE bit is always performed by a write to the data register.
- *
- * The TXE bit is set by hardware and it indicates:
- * ?   The data has been moved from TDR to the shift register and the data transmission has
- *     started.
- * ?   The TDR register is empty.
- * ?   The next data can be written in the USART_DR register without overwriting the
- *     previous data.
- * This flag generates an interrupt if the TXEIE bit is set.
- *
- * When a transmission is taking place, a write instruction to the USART_DR
- * register stores the data in the TDR register and which is copied in the
- * shift register at the end of the current transmission.
- *
- * When no transmission is taking place, a write instruction to the USART_DR
- * register places the data directly in the shift register, the data
- * transmission starts, and the TXE bit is immediately set.
- *
- * If a frame is transmitted (after the stop bit) and the TXE bit is set, the
- * TC bit goes high. An interrupt is generated if the TCIE bit is set in the
- * USART_CR1 register.  After writing the last data into the USART_DR register,
- * it is mandatory to wait for TC=1 before disabling the USART or causing the
- * microcontroller to enter the low power mode (see Figure 241: TC/TXE behavior
- * when transmitting).
- *
- * Clearing the TC bit is performed by the following software sequence:
- * 1.     A read from the USART_SR register
- * 2.     A write to the USART_DR register
- *
- *
- * For now, use 8N1
- *
- * Baud rate is generated by programming the mantissa and fraction values of
- * USARTDIV
- *
- * baud = fck / 16*USARTDIV
- * Fck = PLK1 for USART2 and USART3 = 36MHz
- * Fck = PCLK2 for USART1 = 72MHz
- *
- * Baud    Actual  USARTDIV_36MHZ  Error     USARTDIV_72MHZ Error
- * 2400    2.400   937.5           0%        1875           0%
- * 9600    9.600   234.375         0%        468.75         0%
- * 19200   19.2    117.1875        0%        234.375        0%
- * 57600   57.6    39.0625         0%        78.125         0.%
- * 115200  115.384 19.5            0.15%     39.0625        0%
- * 230400  230.769 9.75            0.16%     19.5           0.16%
- * 460800  461.538 4.875           0.16%     9.75           0.16%
- * 921600  923.076 2.4375          0.16%     4.875          0.16%
- * 225000  2250    1               0%        2              0%
- *
- * */
 #define NR_USARTS           0x3
 
 #ifdef __cplusplus
diff --git a/src/main.cpp b/src/main.cpp
index cf79329..8c90b7d 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -3,9 +3,6 @@
 #include "math.h"

 #include "usb.h"

 

-void setup();

-void loop();

-

 int ledPin = 13;

 uint8_t bytes_in;

 

@@ -26,6 +23,7 @@ void setup()
 

     pinMode(6, PWM);

     pwmWrite(6, 0x8000);

+    pinMode(7, OUTPUT);

 

     Serial2.println("setup end");

 

@@ -37,8 +35,9 @@ void setup()
 

 int toggle = 0;

 

-char* testMsg = "0123456\n";

-void loop() {

+const char* testMsg = "hello world!\n";

+

+static inline void loop() {

     toggle ^= 1;

     digitalWrite(ledPin, toggle);

     delay(1000);

diff --git a/src/wiring/comm/HardwareSerial.cpp b/src/wiring/comm/HardwareSerial.cpp
index 84eb4c7..3d0a0ce 100644
--- a/src/wiring/comm/HardwareSerial.cpp
+++ b/src/wiring/comm/HardwareSerial.cpp
@@ -27,6 +27,7 @@
 #include "HardwareSerial.h"
 #include "usart.h"
 #include "gpio.h"
+#include "timers.h"
 
 #define USART1_TX_PORT             GPIOA_BASE
 #define USART1_TX_PIN              9
@@ -75,6 +76,8 @@ void HardwareSerial::begin(uint32_t baud) {
     case 2:
         gpio_set_mode(USART2_TX_PORT, USART2_TX_PIN, GPIO_MODE_AF_OUTPUT_PP);
         gpio_set_mode(USART2_RX_PORT, USART2_RX_PIN, GPIO_MODE_INPUT_FLOATING);
+        /* Turn off any pwm  */
+        timers_disable_channel(2, 3);
         break;
     case 3:
         gpio_set_mode(USART3_TX_PORT, USART3_TX_PIN, GPIO_MODE_AF_OUTPUT_PP);
diff --git a/src/wiring/time.c b/src/wiring/time.c
index 1a91b5e..164d978 100644
--- a/src/wiring/time.c
+++ b/src/wiring/time.c
@@ -28,7 +28,7 @@
 #include "time.h"
 
 #define CYCLES_PER_MICROSECOND  72
-#define THE_SECRET_TO_LIFE_THE_UNIVERSE_AND_EVERYTHING    42
+#define FUDGE                   42
 
 extern volatile uint32_t systick_timer_millis;
 
@@ -47,26 +47,13 @@ void delay(unsigned long ms)
 }
 
 
-#define MAGIC 4096
-/* HZ = 1000
- * n HZ*/
+
+#if 1
 void delayMicroseconds(uint32_t us) {
     uint32_t target;
     uint32_t last, cur, count;
-
-#if 0
-    asm volatile("mov r0, %[count]     \n\t"
-"1:                                    \n\t"
-            "subs r0, r0, #1           \n\t"
-            "bne 1b"
-                 :
-                 : [count] "r" (count)
-                 : "r0", "cc");
-#endif
-
-#if 1
     /* fudge factor hacky hack hack for function overhead  */
-    target = us * CYCLES_PER_MICROSECOND - THE_SECRET_TO_LIFE_THE_UNIVERSE_AND_EVERYTHING;
+    target = us * CYCLES_PER_MICROSECOND - FUDGE;
 
     /* Get current count */
     last = systick_get_count();
@@ -81,5 +68,5 @@ void delayMicroseconds(uint32_t us) {
         }
         last = cur;
     }
-#endif
 }
+#endif
diff --git a/src/wiring/time.h b/src/wiring/time.h
index a97310a..68b3901 100644
--- a/src/wiring/time.h
+++ b/src/wiring/time.h
@@ -41,6 +41,20 @@ void delay(unsigned long ms);
 /* Delay for us microseconds  */
 void delayMicroseconds(uint32_t us);
 
+#if 0
+static inline void delay_us(uint32 us) {
+    us *= 12;
+    asm volatile("mov  r0, %[us]        \n\t"
+                 "subs r0, #2 \n\t"
+"1:                                    \n\t"
+                  "subs r0, r0, #1           \n\t"
+                  "bne 1b"
+                 :
+                 : [us] "r" (us)
+                 : "r0", "cc");
+
+}
+#endif
 #ifdef __cplusplus
 } // extern "C"
 #endif
diff --git a/src/wiring/wiring.c b/src/wiring/wiring.c
index cecca20..04de78a 100644
--- a/src/wiring/wiring.c
+++ b/src/wiring/wiring.c
@@ -47,13 +47,12 @@ void init(void) {
 
    gpio_init();
 
-   /* off for debug  */
-//   adc_init();
+   adc_init();
 
    timer_init(1, 1);
-//   timer_init(2, 1);
-//   timer_init(3, 1);
-//   timer_init(4, 1);
+   timer_init(2, 1);
+   timer_init(3, 1);
+   timer_init(4, 1);
 }
 
 void NVIC_Configuration(void) {