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fix tm1637: always send 3 command types

This commit is contained in:
King Kévin 2017-05-04 12:06:42 +02:00
parent bee5a1a827
commit 97e8de0bc9
2 changed files with 49 additions and 62 deletions
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100
lib/led_tm1637.c
View File

@ -12,13 +12,14 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>. * along with this program. If not, see <http://www.gnu.org/licenses/>.
* *
*/ */
/** library to communicate with a Titan Micro TM1637 IC attached to a 4-digit 7-segment (code) /** library to communicate with a Titan Micro TM1637 IC attached to a 7-segment displays (code)
* @file led_tm1637.c * @file led_tm1637.c
* @author King Kévin <kingkevin@cuvoodoo.info> * @author King Kévin <kingkevin@cuvoodoo.info>
* @date 2017 * @date 2017
* @note peripherals used: GPIO @ref led_tm1637_gpio, timer @ref led_tm1637_timer * @note peripherals used: GPIO @ref led_tm1637_gpio, timer @ref led_tm1637_timer
* @note the protocol is very similar to I2C but incompatible for the following reasons: the capacitance is too large for open-drain type output with weak pull-up resistors (push-pull needs to be used, preventing to get ACKs since no indication of the ACK timing is provided); the devices doesn't use addresses; the STM32 I2C will switch to receiver mode when the first sent byte (the I2C address) has last bit set to 1 (such as for address commands with B7=1 where B7 is transmitted last), preventing to send further bytes (the data byte after the address) * @note only 4-digit 7-segment displays are considered as this is the most common case
* @warning all calls are blocking * @warning all calls are blocking
* @note the protocol is very similar to I2C but incompatible for the following reasons: the pin capacitance is too large for open-drain type output with weak pull-up resistors (push-pull needs to be used, preventing to get ACKs since no indication of the ACK timing is provided); the devices doesn't use addresses; the STM32 I2C will switch to receiver mode when the first sent byte (the I2C address) has last bit set to 1 (such as for address commands with B7=1 where B7 is transmitted last), preventing to send further bytes (the data byte after the address)
* *
* bit vs segment: 0bpgfedcba * bit vs segment: 0bpgfedcba
* +a+ * +a+
@ -30,7 +31,7 @@
/* standard libraries */ /* standard libraries */
#include <stdint.h> // standard integer types #include <stdint.h> // standard integer types
#include <stdlib.h> // general utilities #include <stdlib.h> // memory utilities
#include <string.h> // string utilities #include <string.h> // string utilities
/* STM32 (including CM3) libraries */ /* STM32 (including CM3) libraries */
@ -58,9 +59,7 @@
/** @} */ /** @} */
/** display brightness */ /** display brightness */
static enum led_tm1637_brightness_t display_brightness = LED_TM1637_14DIV16; enum led_tm1637_brightness_t display_brightness = LED_TM1637_14DIV16;
/** if display is on */
static bool display_on = false;
/** ASCII characters encoded for the 7 segments digit block /** ASCII characters encoded for the 7 segments digit block
* @note starts with space * @note starts with space
@ -198,14 +197,15 @@ static inline void led_tm1637_tick(void)
* @return if write succeeded * @return if write succeeded
* @note includes start and stop conditions * @note includes start and stop conditions
*/ */
static bool led_tm1637_write(const uint8_t* data, size_t length) static bool led_tm1637_write(const uint8_t* data, uint8_t length)
{ {
bool to_return = true; // return if write succeeded bool to_return = true; // return if write succeeded
if (data==NULL || length==0) { // verify there it data to be read if (NULL==data || 0==length) { // verify there it data to be read
return false; return false;
} }
// enable timer for signal generation // enable timer for signal generation
gpio_set_mode(GPIO(LED_TM1637_DIO_PORT), GPIO_MODE_OUTPUT_2_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO(LED_TM1637_DIO_PIN)); // ensure we can output to sent start condition
timer_set_counter(TIM(LED_TM1637_TIMER), 0); // reset timer counter timer_set_counter(TIM(LED_TM1637_TIMER), 0); // reset timer counter
timer_enable_counter(TIM(LED_TM1637_TIMER)); // enable timer to generate timing timer_enable_counter(TIM(LED_TM1637_TIMER)); // enable timer to generate timing
led_tm1637_tick(); // wait to enforce minimum time since last write led_tm1637_tick(); // wait to enforce minimum time since last write
@ -216,8 +216,9 @@ static bool led_tm1637_write(const uint8_t* data, size_t length)
gpio_clear(GPIO(LED_TM1637_CLK_PORT), GPIO(LED_TM1637_CLK_PIN)); // put CLK low gpio_clear(GPIO(LED_TM1637_CLK_PORT), GPIO(LED_TM1637_CLK_PIN)); // put CLK low
// send data bytes (MSb first) // send data bytes (MSb first)
for (size_t i=0; i<length; i++) { // send all bytes for (uint8_t i=0; i<length; i++) { // send all bytes
uint8_t byte = data[i]; uint8_t byte = data[i];
gpio_set_mode(GPIO(LED_TM1637_DIO_PORT), GPIO_MODE_OUTPUT_2_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO(LED_TM1637_DIO_PIN)); // switch DIO to output to send bits
for (uint8_t b=0; b<8; b++) { // send all bits for (uint8_t b=0; b<8; b++) { // send all bits
if (byte&0x1) { // send a 1 if (byte&0x1) { // send a 1
gpio_set(GPIO(LED_TM1637_DIO_PORT), GPIO(LED_TM1637_DIO_PIN)); // put DIO high gpio_set(GPIO(LED_TM1637_DIO_PORT), GPIO(LED_TM1637_DIO_PIN)); // put DIO high
@ -239,11 +240,10 @@ static bool led_tm1637_write(const uint8_t* data, size_t length)
} }
led_tm1637_tick(); // wait for next tick led_tm1637_tick(); // wait for next tick
gpio_clear(GPIO(LED_TM1637_CLK_PORT), GPIO(LED_TM1637_CLK_PIN)); // put CLK low gpio_clear(GPIO(LED_TM1637_CLK_PORT), GPIO(LED_TM1637_CLK_PIN)); // put CLK low
gpio_set_mode(GPIO(LED_TM1637_DIO_PORT), GPIO_MODE_OUTPUT_2_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO(LED_TM1637_DIO_PIN)); // switch DIO back to output to send next byte
} }
// send stop condition // send stop condition
gpio_set_mode(GPIO(LED_TM1637_DIO_PORT), GPIO_MODE_OUTPUT_2_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO(LED_TM1637_DIO_PIN)); // ensure DIO is output (in case no ACK as been received gpio_set_mode(GPIO(LED_TM1637_DIO_PORT), GPIO_MODE_OUTPUT_2_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO(LED_TM1637_DIO_PIN)); // switch DIO to output to send stop condition
led_tm1637_tick(); // wait for next tick led_tm1637_tick(); // wait for next tick
gpio_set(GPIO(LED_TM1637_CLK_PORT), GPIO(LED_TM1637_CLK_PIN)); // put CLK high gpio_set(GPIO(LED_TM1637_CLK_PORT), GPIO(LED_TM1637_CLK_PIN)); // put CLK high
led_tm1637_tick(); // wait for next tick led_tm1637_tick(); // wait for next tick
@ -253,58 +253,55 @@ static bool led_tm1637_write(const uint8_t* data, size_t length)
return to_return; return to_return;
} }
bool led_tm1637_on(void) /** write commands on bus to send data
* @param[in] address_command data data to send (including address as first byte)
* @param[in] length length of data
* @return if send succeeded
*/
static bool led_tm1637_send_data(uint8_t* address_command, uint8_t length)
{ {
uint8_t data[] = { 0x88+display_brightness }; // command to turn display on (use set brightness) // sanity check
bool to_return = false; // result to return if (0==length && NULL==address_command) {
if (led_tm1637_write(data,LENGTH(data))) { // send command return false;
display_on = true; // remember display is on
to_return = true; // command succeeded
} }
return to_return; // return result
uint8_t data_command[] = { 0x40 }; // data command: write data, automatic address adding, normal
uint8_t display_command[] = { 0x88+(display_brightness&0x0f) }; // display command: turn display on and set brightness
if (led_tm1637_write(data_command, LENGTH(data_command)) && led_tm1637_write(address_command, length) && led_tm1637_write(display_command, LENGTH(display_command))) { // send commands
return true;
}
return false;
} }
bool led_tm1637_off(void) bool led_tm1637_off(void)
{ {
uint8_t data[] = { 0x80+display_brightness }; // command to turn display off (use set brightness) // note: while the TM1637 could recognize the display command thanks to the first two bits, we still need to send the data and address command first
if (led_tm1637_write(data,LENGTH(data))) { // send command uint8_t data_command[] = { 0x40 }; // data command: write data, automatic address adding, normal
display_on = false; // remember display is off uint8_t address_command[] = { 0xc0, 0x00, 0x00, 0x00, 0x00 }; // address command: clear all (if bit 7 of byte 4 is set switching off doesn't work correctly, I don't know why)
return true; // command succeeded uint8_t display_command[] = { 0x80 }; // display command: turn display off (we don't care about the brightness since it's set when turned on)
}
return false; // return result if (led_tm1637_write(data_command,LENGTH(data_command)) && led_tm1637_write(address_command, LENGTH(address_command)) && led_tm1637_write(display_command, LENGTH(display_command))) { // send commands
} return true;
bool led_tm1637_brightness(enum led_tm1637_brightness_t brightness)
{
display_brightness = brightness; // save brightness
if (display_on) { // adjust brightness if display is on
return led_tm1637_on(); // adjust brightness
} else {
return true; // command succeeded
} }
return false; return false;
} }
void led_tm1637_brightness(enum led_tm1637_brightness_t brightness)
{
display_brightness = (brightness&0x0f); // save brightness
}
bool led_tm1637_number(uint16_t number) bool led_tm1637_number(uint16_t number)
{ {
uint8_t write_data[] = { 0x40 }; // command: write data, automatic address adding, normal uint8_t data[] = { 0xc0, ascii_7segments[((number/1000)%10)+'0'-' '], ascii_7segments[((number/100)%10)+'0'-' '], ascii_7segments[((number/10)%10)+'0'-' '], ascii_7segments[((number/1)%10)+'0'-' '] }; // encode number on 4 digits
uint8_t data[] = { 0xc0, ascii_7segments[((number/1000)%10)+'0'-' '], ascii_7segments[((number/100)%10)+'0'-' '], ascii_7segments[((number/10)%10)+'0'-' '], ascii_7segments[((number/1)%10)+'0'-' '] }; // set address C0H and add data return led_tm1637_send_data(data, LENGTH(data)); // transmit data
if (led_tm1637_write(write_data,LENGTH(write_data)) && led_tm1637_write(data,LENGTH(data))) { // send commands
return true;
}
return false;
} }
bool led_tm1637_time(uint8_t hours, uint8_t minutes) bool led_tm1637_time(uint8_t hours, uint8_t minutes)
{ {
uint8_t write_data[] = { 0x40 }; // command: write data, automatic address adding, normal uint8_t data[] = { 0xc0, ascii_7segments[((hours/10)%10)+'0'-' '], ascii_7segments[((hours/1)%10)+'0'-' ']|0x80, ascii_7segments[((minutes/10)%10)+'0'-' '], ascii_7segments[((minutes/1)%10)+'0'-' '] }; // encode time on 4 digits
uint8_t data[] = { 0xc0, ascii_7segments[((hours/10)%10)+'0'-' '], ascii_7segments[((hours/1)%10)+'0'-' ']|0x80, ascii_7segments[((minutes/10)%10)+'0'-' '], ascii_7segments[((minutes/1)%10)+'0'-' '] }; // set address C0H and add data return led_tm1637_send_data(data, LENGTH(data)); // transmit data
if (led_tm1637_write(write_data,LENGTH(write_data)) && led_tm1637_write(data,LENGTH(data))) { // send commands
return true;
}
return false;
} }
bool led_tm1637_text(char* text) bool led_tm1637_text(char* text)
@ -317,11 +314,6 @@ bool led_tm1637_text(char* text)
return false; return false;
} }
} }
uint8_t write_data[] = { 0x40 }; // command: write data, automatic address adding, normal uint8_t data[] = { 0xc0, ascii_7segments[(text[0]&0x7f)-' ']|(text[0]&0x80), ascii_7segments[(text[1]&0x7f)-' ']|(text[1]&0x80), ascii_7segments[(text[2]&0x7f)-' ']|(text[2]&0x80), ascii_7segments[(text[3]&0x7f)-' ']|(text[3]&0x80) }; // encode text on 7 digits
uint8_t data[] = { 0xc0, ascii_7segments[(text[0]&0x7f)-' ']|(text[0]&0x80), ascii_7segments[(text[1]&0x7f)-' ']|(text[1]&0x80), ascii_7segments[(text[2]&0x7f)-' ']|(text[2]&0x80), ascii_7segments[(text[3]&0x7f)-' ']|(text[3]&0x80) }; // set address C0H and add data return led_tm1637_send_data(data, LENGTH(data)); // transmit data
if (led_tm1637_write(write_data,LENGTH(write_data)) && led_tm1637_write(data,LENGTH(data))) { // send commands
return true;
}
return false;
} }

11
lib/led_tm1637.h
View File

@ -12,11 +12,12 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>. * along with this program. If not, see <http://www.gnu.org/licenses/>.
* *
*/ */
/** library to communicate with a Titan Micro TM1637 IC attached to a 4-digit 7-segment (API) /** library to communicate with a Titan Micro TM1637 IC attached to a 7-segment displays (API)
* @file led_tm1637.h * @file led_tm1637.h
* @author King Kévin <kingkevin@cuvoodoo.info> * @author King Kévin <kingkevin@cuvoodoo.info>
* @date 2017 * @date 2017
* @note peripherals used: GPIO @ref led_tm1637_gpio, timer @ref led_tm1637_timer * @note peripherals used: GPIO @ref led_tm1637_gpio, timer @ref led_tm1637_timer
* @note only 4-digit 7-segment displays are considered as this is the most common case
* @warning all calls are blocking * @warning all calls are blocking
*/ */
#pragma once #pragma once
@ -40,16 +41,11 @@ void led_tm1637_setup(void);
/** switch display on /** switch display on
* @return if transmission succeeded * @return if transmission succeeded
*/ */
bool led_tm1637_on(void);
/** switch display off
* @return if transmission succeeded
*/
bool led_tm1637_off(void); bool led_tm1637_off(void);
/** set display brightness /** set display brightness
* @param[in] brightness brightness level to set * @param[in] brightness brightness level to set
* @return if transmission succeeded
*/ */
bool led_tm1637_brightness(enum led_tm1637_brightness_t brightness); void led_tm1637_brightness(enum led_tm1637_brightness_t brightness);
/** display number /** display number
* @param[in] number number to display (0-9999) * @param[in] number number to display (0-9999)
* @return if transmission succeeded * @return if transmission succeeded
@ -68,4 +64,3 @@ bool led_tm1637_time(uint8_t hours, uint8_t minutes);
* @return if transmission succeeded * @return if transmission succeeded
*/ */
bool led_tm1637_text(char* text); bool led_tm1637_text(char* text);