tm1637 signs of life, terminal builtin cmds

[cortex-from-scratch] / drivers / tm1637.c

diff --git a/drivers/tm1637.c b/drivers/tm1637.c
index a4e3842..517e0cf 100644 (file)
--- a/drivers/tm1637.c
+++ b/drivers/tm1637.c
@@ -5,8 +5,13 @@
  * Initial version 
  * 
  * $DESCRIPTION$
- * Basic driver for the TM1637. The TM1637 is 7 segment
- * ledclock peripheral. Communication is over I2C.
+ * Basic driver for the TM1637. The TM1637 is 8 segment
+ * ledclock peripheral. Communication is similar to I2C,
+ * but not completely. There is no address selecting.
+ *
+ * Alternative I2C protocol : (W)rite or (R)ead
+ * | Start | ADDRESS | W | ACK/NACK | DATA | ACK/NACK | (d+a*n) | St
+ * | Start | ADDRESS | R | ACK/NACK | DATA | ACK/NACK | (d+a*n) | St
  *
  * */
 
@@ -19,26 +24,154 @@
 
 #include <lib/regfunc.h>
 #include <lib/string.h>
+#include <lib/stdio.h>
 
 #include <drivers/tm1637.h>
 
+#define TIMEOUT 1000
+
+#define DATASET        0x40
+#define CONTROL        0x80
+#define SETADDR        0xC0
+
+#define DISPLAY_ON     0x8F
+#define DISPLAY_OFF    0x11
+
+/* STM32F1 microcontrollers do not provide the ability to pull-up SDA and SCL lines. Their
+GPIOs must be configured as open-drain. So, you have to add two additional resistors to
+pull-up I2C lines. Something between 4K and 10K is a proven value.
+*/
 
 void tm1637_init() {
 
  /* Program the peripheral input clock in I2C_CR2 Register in order to generate correct timings
- Configure the clock control registers
- Configure the rise time register
+ Configure the clock control registers CCR
+ Configure the rise time register TRIS
  Program the I2C_CR1 register to enable the peripheral
- Set the START bit in the I2C_CR1 register to generate a Start condition 
 
  ENABLE GPIOB6 and B7*/
 
- //regw_u8(RCC_APB1ENR, 0x1, 21, SETBIT);
- //regw_u32(RCC_APB2ENR, 0x1, 3, SETBIT);
+ regw_u32(RCC_APB1ENR, 0x1, 21, SETBIT);
+ regw_u32(RCC_APB2ENR, 0x1, 3, SETBIT);
  // //regw_u8(AFIO_EVCR, 0x89, 0, SETBIT);// set event control register, output on ?
  
- // regw_u32(GPIOB_CRL, 0xEE444444, 0, OWRITE);
+ regw_u32(GPIOB_CRL, 0xEE444444, 0, OWRITE);
+
+ regw_u32(I2C_CR2, 0x2, 0, OWRITE); //2 MHz 
+ regw_u8(I2C_TRISE, 0x3, 0, OWRITE); // MAX = 1000ns, TPCLK1 = 500ns (+1)
+ regw_u32(I2C_CCR, 0x000A, 0, OWRITE); // standard mode， output 100 kHz (100hz* / perip)
  
+ regw_u32(I2C_CR1, 0x1, 0, OWRITE); // enable
+
+}
+
+static void start_condition() {
+
+       regw_u32(I2C_CR1, 0x1, 8, SETBIT); //start
+
+}
+
+static void stop_condition() {
+
+       regw_u32(I2C_CR1, 0x1, 9, SETBIT); //stop
+}
+
+int ack_recv() {
+
+       int cnt = 0;
+       while(!(*I2C_SR1 & 0x1)) {
+               cnt++;
+               if (cnt > TIMEOUT)
+                       return 0;
+       }
+
+       return 1;
+
+}
+
+int delay() {
+
+       int a = 0;
+       for (int i = 0; i < TIMEOUT; i++)
+               a++;
+}
+
+void tm1637_start() {
+
+//     regw_u32(I2C_CR1, 0x1, 8, SETBIT);
+//     uint32_t read_status = *I2C_SR1;
+
+//     regw_u32(I2C_DR, DATASET, 0, OWRITE); 
+       // conform DATA
+//     read_status = *I2C_SR1;
+//     read_status = *I2C_SR2;
+
+       uint32_t statusr;
+
+       start_condition();
+       //uint32_t statusr = *I2C_SR1; // clear start_signal
+       regw_u32(I2C_DR, 0x40, 0, OWRITE); // write to address CMD
+       if(!ack_recv())
+               cputs("TIMEOUT!");
+       //statusr = *I2C_SR1;
+       //statusr = *I2C_SR2;
+       stop_condition();
+
+       //delay();
+
+       start_condition();
+       //statusr = *I2C_SR1; // clear start_signal
+       regw_u32(I2C_DR, 0xC1, 0, OWRITE);
+       if(!ack_recv())
+               cputs("TIMEOUT2!");
+       //statusr = *I2C_SR1;
+       //statusr = *I2C_SR2;
+       regw_u32(I2C_DR, 0x7D, 0, OWRITE);
+       if(!ack_recv())
+               cputs("TIMEOUT3!");
+       stop_condition();
+
+       delay();
+
+       start_condition();
+       statusr = *I2C_SR1;
+       regw_u32(I2C_DR, DISPLAY_ON, 0, OWRITE);
+       if(!ack_recv())
+               cputs("TIMEOUT4!");
+       stop_condition();
+
+
+       /* regw_u32(I2C_CR1, 0x1, 8, SETBIT); //start
+       uint32_t read_status = *I2C_SR1; 
+       regw_u32(I2C_DR, 0x40, 0, OWRITE); // write to address CMD
+       read_status = *I2C_SR1;
+       read_status = *I2C_SR2;
+       regw_u32(I2C_CR1, 0x1, 9, SETBIT); //stop
+       read_status = *I2C_SR1;
+
+       regw_u32(I2C_CR1, 0x1, 8, SETBIT); //start
+       read_status = *I2C_SR1;
+       regw_u32(I2C_DR, 0xC1, 0, OWRITE); // segment address
+       read_status = *I2C_SR1;
+       read_status = *I2C_SR2;
+       regw_u32(I2C_DR, 0x7D, 0, OWRITE); // write a six
+
+       regw_u32(I2C_CR1, 0x1, 9, SETBIT); //stop
+       read_status = *I2C_SR1;
+
+       regw_u32(I2C_CR1, 0x1, 8, SETBIT); //start
+       read_status = *I2C_SR1;
+
+       regw_u32(I2C_DR, DISPLAY_ON, 0, OWRITE);
+       read_status = *I2C_SR1;
+       regw_u32(I2C_CR1, 0x1, 9, SETBIT); //stop */
 
 }
 
+void tm1637_stop() {
+
+       //regw_u32(I2C_CR1, 0x0, 9, SETBIT);
+}
+
+
+