* 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
*
* */
#include <lib/regfunc.h>
#include <lib/string.h>
+#include <lib/stdio.h>
#include <drivers/tm1637.h>
+#define TIMEOUT 5000
+
+#define DOT true
+#define NODOT false
+
+
+/*
+0 = 0x00
+1 = 0x60
+2 = 0xDA
+3 = 0xF2
+4 = 0x66
+5 = 0xB6
+6 = 0xBE
+7 = 0xE0
+8 = 0xFF
+9 = 0xF6
+*/
+
+/* 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.
+*/
+
+/* BIG ENDIAN! */
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
+
+}
+
+void tm1637_reset() {
+
+ regw_u32(RCC_APB1RSTR, 0x1, 21, SETBIT);
+
+ regw_u32(RCC_APB1RSTR, 0x00000000, 0, OWRITE); // clr
+ //regw_u32(RCC_APB2ENR, 0x1, 3, SETBIT);
+ // //regw_u8(AFIO_EVCR, 0x89, 0, SETBIT);// set event control register, output on ?
+
+ regw_u32(RCC_APB1ENR, 0x1, 21, SETBIT);
+ //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
+}
+
+static int buf_empty() {
+ int cnt = 0;
+ while(!(*I2C_SR1 & 0x80)) {
+ cnt++;
+ if (cnt > TIMEOUT) {
+ return 0;
+ }
+ }
+ return 1;
+}
+
+/* Wait for an acknowledge from the peripheral */
+int ack_recv() {
+ int cnt = 0;
+ while(!(*I2C_SR1 & 0x2)) {
+ cnt++;
+ if (cnt > TIMEOUT)
+ return 0;
+ }
+ uint32_t a = *I2C_SR2; // need to read SR2 register!
+ return 1;
+
+}
+
+/* Similar, but SR2 register is not read */
+int ack10_recv() {
+ int cnt = 0;
+ while(!(*I2C_SR1 & 0x8)) {
+ cnt++;
+ if (cnt > TIMEOUT)
+ return 0;
+ }
+ return 1;
+
+}
+
+int idle() {
+ int cnt = 0;
+ while(*I2C_SR2 & 0x2) {
+ cnt++;
+ if (cnt > TIMEOUT)
+ return 0;
+ }
+ return 1;
}
+int delay() {
+
+ int a = 0;
+ for (int i = 0; i < TIMEOUT; i++)
+ a++;
+}
+
+void set_display(bool on, uint8_t degree) {
+
+ start_condition();
+
+ regw_u32(I2C_DR, 0xF1, 0, OWRITE);
+ if(!ack_recv())
+ cputs("Can't switch on display!");
+ stop_condition();
+
+ // reset bus
+ regw_u32(I2C_CR1, 0x1, 15, SETBIT);
+
+}
+
+
+void set_segment(int offset, char value, bool dot) {
+
+ int (*ack)() = ack_recv; /* Scary function pointer :D */
+
+
+ if (offset > 3) {
+ cputs("Offset incorrect");
+ }
+
+ if (dot) {
+ value = value | 0x1;
+ }
+ int start_pos_cmd = 0x03 | (offset & 0x01) << 7 | (offset & 0x2) << 5 ;
+
+ start_condition();
+ regw_u32(I2C_DR, 0x20, 0, OWRITE);
+ if(!ack_recv())
+ cputs("Error: initiating write for start segment \n");
+
+ stop_condition();
+
+ if(!idle())
+ cputs("Error: timeout");
+
+
+ start_condition();
+ regw_u32(I2C_DR, start_pos_cmd, 0, OWRITE);
+ if(!ack())
+ cputs("Error: Can't set start segment \n");
+
+ stop_condition();
+ regw_u32(I2C_CR1, 0x1, 15, SETBIT);
+
+ tm1637_reset();
+
+// if (value & 0xF0)
+// ack = &ack10_recv;
+
+ start_condition();
+ regw_u32(I2C_DR, value, 0, OWRITE); // use ack10 if higher
+ if(!ack_recv())
+ cputs("Error: can't set location\n");
+ stop_condition();
+
+ regw_u32(I2C_CR1, 0x1, 15, SETBIT);
+
+ tm1637_reset();
+}
+
+
+
+void tm1637_start() {
+
+unsigned char display_number[10] = {0xFC, 0x60, 0xDA, 0xF2, 0x66, 0xB6, 0xBE, 0xE0, 0xFE, 0xF6};
+
+
+ char love[4] = { 0x1C, 0xFC, 0x7C, 0x9E };
+
+ for (int i = 0; i < 4; i++) {
+ set_segment(i, love[i], NODOT);
+ }
+
+ set_display(true, 0);
+
+}
+
+
projects / cortex-from-scratch / blobdiff