CuVoodoo STM32F1 firmware template
led_tm1637.c
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1 /* This program is free software: you can redistribute it and/or modify
2  * it under the terms of the GNU General Public License as published by
3  * the Free Software Foundation, either version 3 of the License, or
4  * (at your option) any later version.
5  *
6  * This program is distributed in the hope that it will be useful,
7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
9  * GNU General Public License for more details.
10  *
11  * You should have received a copy of the GNU General Public License
12  * along with this program. If not, see <http://www.gnu.org/licenses/>.
13  *
14  */
31 /* standard libraries */
32 #include <stdint.h> // standard integer types
33 #include <stdlib.h> // general utilities
34 #include <string.h> // string utilities
35 
36 /* STM32 (including CM3) libraries */
37 #include <libopencmsis/core_cm3.h> // Cortex M3 utilities
38 #include <libopencm3/stm32/rcc.h> // real-time control clock library
39 #include <libopencm3/stm32/gpio.h> // general purpose input output library
40 #include <libopencm3/stm32/timer.h> // timer library
41 
42 #include "global.h" // global utilities
43 #include "led_tm1637.h" // TM1637 header and definitions
44 
48 #define LED_TM1637_CLK_PORT B
49 #define LED_TM1637_CLK_PIN 6
50 #define LED_TM1637_DIO_PORT B
51 #define LED_TM1637_DIO_PIN 7
57 #define LED_TM1637_TIMER 3
61 static enum led_tm1637_brightness_t display_brightness = LED_TM1637_14DIV16;
62 
63 static bool display_on = false;
64 
68 static const uint8_t ascii_7segments[] = {
69  0x00, // 0b00000000 space
70  0x30, // 0b00110000 ! (I)
71  0x22, // 0b00100010 "
72  0x5c, // 0b01011100 # (o)
73  0x6d, // 0b01101101 $ (s)
74  0x52, // 0b01010010 % (/)
75  0x7d, // 0b01111101 & (6)
76  0x20, // 0b00100000 '
77  0x39, // 0b00111001 ( ([)
78  0x0f, // 0b00001111 )
79  0x70, // 0b01110000 *
80  0x46, // 0b01000110 +
81  0x10, // 0b00010000 ,
82  0x40, // 0b01000000 -
83  0x10, // 0b00010000 . (,)
84  0x52, // 0b01010010 /
85  0x3f, // 0b00111111 0
86  0x06, // 0b00000110 1
87  0x5b, // 0b01011011 2
88  0x4f, // 0b01001111 3
89  0x66, // 0b01100110 4
90  0x6d, // 0b01101101 5
91  0x7d, // 0b01111101 6
92  0x07, // 0b00000111 7
93  0x7f, // 0b01111111 8
94  0x6f, // 0b01101111 9
95  0x48, // 0b01001000 : (=)
96  0x48, // 0b01001000 ; (=)
97  0x58, // 0b01011000 <
98  0x48, // 0b01001000 =
99  0x4c, // 0b01001100 >
100  0x53, // 0b01010011 ?
101  0x7b, // 0b01111011 @
102  0x77, // 0b01110111 A
103  0x7f, // 0b01111111 B
104  0x39, // 0b00111001 C
105  0x5e, // 0b01011110 D
106  0x79, // 0b01111001 E
107  0x71, // 0b01110001 F
108  0x3d, // 0b00111101 G
109  0x76, // 0b01110110 H
110  0x30, // 0b00110000 I
111  0x1e, // 0b00011110 J
112  0x76, // 0b01110110 K
113  0x38, // 0b00111000 L
114  0x37, // 0b00110111 M
115  0x37, // 0b00110111 N
116  0x3f, // 0b00111111 O
117  0x73, // 0b01110011 P
118  0x6b, // 0b01101011 Q
119  0x33, // 0b00110011 R
120  0x6d, // 0b01101101 S
121  0x78, // 0b01111000 T
122  0x3e, // 0b00111110 U
123  0x3e, // 0b00111110 V (U)
124  0x3e, // 0b00111110 W (U)
125  0x76, // 0b01110110 X (H)
126  0x6e, // 0b01101110 Y
127  0x5b, // 0b01011011 Z
128  0x39, // 0b00111001 [
129  0x64, // 0b01100100 '\'
130  0x0f, // 0b00001111 /
131  0x23, // 0b00100011 ^
132  0x08, // 0b00001000 _
133  0x02, // 0b00000010 `
134  0x5f, // 0b01011111 a
135  0x7c, // 0b01111100 b
136  0x58, // 0b01011000 c
137  0x5e, // 0b01011110 d
138  0x7b, // 0b01111011 e
139  0x71, // 0b01110001 f
140  0x6f, // 0b01101111 g
141  0x74, // 0b01110100 h
142  0x10, // 0b00010000 i
143  0x0c, // 0b00001100 j
144  0x76, // 0b01110110 k
145  0x30, // 0b00110000 l
146  0x54, // 0b01010100 m
147  0x54, // 0b01010100 n
148  0x5c, // 0b01011100 o
149  0x73, // 0b01110011 p
150  0x67, // 0b01100111 q
151  0x50, // 0b01010000 r
152  0x6d, // 0b01101101 s
153  0x78, // 0b01111000 t
154  0x1c, // 0b00011100 u
155  0x1c, // 0b00011100 v (u)
156  0x1c, // 0b00011100 w (u)
157  0x76, // 0b01110110 x
158  0x6e, // 0b01101110 y
159  0x5b, // 0b01011011 z
160  0x39, // 0b00111001 { ([)
161  0x30, // 0b00110000 |
162  0x0f, // 0b00001111 } ([)
163  0x40, // 0b01000000 ~
164 };
165 
167 {
168  // configure GPIO for CLK and DIO signals
169  rcc_periph_clock_enable(RCC_GPIO(LED_TM1637_CLK_PORT)); // enable clock for GPIO peripheral
170  gpio_set(GPIO(LED_TM1637_CLK_PORT), GPIO(LED_TM1637_CLK_PIN)); // idle high
171  gpio_set_mode(GPIO(LED_TM1637_CLK_PORT), GPIO_MODE_OUTPUT_10_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO(LED_TM1637_CLK_PIN)); // master start the communication (capacitance is to large for open drain), only switch to input for ack from slave
172  rcc_periph_clock_enable(RCC_GPIO(LED_TM1637_DIO_PORT)); // enable clock for GPIO peripheral
173  gpio_set(GPIO(LED_TM1637_DIO_PORT), GPIO(LED_TM1637_DIO_PIN)); // idle high
174  gpio_set_mode(GPIO(LED_TM1637_DIO_PORT), GPIO_MODE_OUTPUT_10_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO(LED_TM1637_DIO_PIN)); // master start the communication (capacitance is to large for open drain), only switch to input for ack from slave
175  // first clock then data high also stands for stop condition
176 
177  // setup timer to create signal timing (each tick is used for a single GPIO transition)
178  rcc_periph_clock_enable(RCC_TIM(LED_TM1637_TIMER)); // enable clock for timer block
179  timer_reset(TIM(LED_TM1637_TIMER)); // reset timer state
180  timer_set_mode(TIM(LED_TM1637_TIMER), TIM_CR1_CKD_CK_INT, TIM_CR1_CMS_EDGE, TIM_CR1_DIR_UP); // set timer mode, use undivided timer clock, edge alignment (simple count), and count up
181  timer_set_prescaler(TIM(LED_TM1637_TIMER), 0); // don't prescale to get most precise timing ( 1/(72E6/1/(2**16))=0.91 ms > 0.5 us )
182  timer_set_period(TIM(LED_TM1637_TIMER), 500); // set the clock frequency (emprical value until the signal starts to look bad)
183  timer_clear_flag(TIM(LED_TM1637_TIMER), TIM_SR_UIF); // clear flag
184  timer_update_on_overflow(TIM(LED_TM1637_TIMER)); // only use counter overflow as UEV source (use overflow as start time or timeout)
185 }
186 
189 static inline void led_tm1637_tick(void)
190 {
191  while (!timer_get_flag(TIM(LED_TM1637_TIMER), TIM_SR_UIF)); // wait until counter overflow update event happens
192  timer_clear_flag(TIM(LED_TM1637_TIMER), TIM_SR_UIF); // clear event flag
193 }
194 
201 static bool led_tm1637_write(const uint8_t* data, size_t length)
202 {
203  bool to_return = true; // return if write succeeded
204  if (data==NULL || length==0) { // verify there it data to be read
205  return false;
206  }
207 
208  // enable timer for signal generation
209  timer_set_counter(TIM(LED_TM1637_TIMER), 0); // reset timer counter
210  timer_enable_counter(TIM(LED_TM1637_TIMER)); // enable timer to generate timing
211  led_tm1637_tick(); // wait to enforce minimum time since last write
212 
213  // send start condition (DIO then CLK low)
214  gpio_clear(GPIO(LED_TM1637_DIO_PORT), GPIO(LED_TM1637_DIO_PIN)); // put DIO low
215  led_tm1637_tick(); // wait for next tick
216  gpio_clear(GPIO(LED_TM1637_CLK_PORT), GPIO(LED_TM1637_CLK_PIN)); // put CLK low
217 
218  // send data bytes (MSb first)
219  for (size_t i=0; i<length; i++) { // send all bytes
220  uint8_t byte = data[i];
221  for (uint8_t b=0; b<8; b++) { // send all bits
222  if (byte&0x1) { // send a 1
223  gpio_set(GPIO(LED_TM1637_DIO_PORT), GPIO(LED_TM1637_DIO_PIN)); // put DIO high
224  } else {
225  gpio_clear(GPIO(LED_TM1637_DIO_PORT), GPIO(LED_TM1637_DIO_PIN)); // put DIO low
226  }
227  byte >>= 1; // shift data
228  led_tm1637_tick(); // wait for next tick
229  gpio_set(GPIO(LED_TM1637_CLK_PORT), GPIO(LED_TM1637_CLK_PIN)); // put CLK high
230  led_tm1637_tick(); // wait for next tick (no DIO transition when CLK is high)
231  gpio_clear(GPIO(LED_TM1637_CLK_PORT), GPIO(LED_TM1637_CLK_PIN)); // put CLK low
232  }
233  gpio_set_mode(GPIO(LED_TM1637_DIO_PORT), GPIO_MODE_INPUT, GPIO_CNF_INPUT_FLOAT, GPIO(LED_TM1637_DIO_PIN)); // switch DIO as input to read ACK
234  led_tm1637_tick(); // wait for next tick (when the slave should ACK)
235  gpio_set(GPIO(LED_TM1637_CLK_PORT), GPIO(LED_TM1637_CLK_PIN)); // put CLK high
236  if (gpio_get(GPIO(LED_TM1637_DIO_PORT), GPIO(LED_TM1637_DIO_PIN))) { // no ACK received
237  to_return = false; // remember there was an error
238  break; // stop sending bytes
239  }
240  led_tm1637_tick(); // wait for next tick
241  gpio_clear(GPIO(LED_TM1637_CLK_PORT), GPIO(LED_TM1637_CLK_PIN)); // put CLK low
242  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
243  }
244 
245  // send stop condition
246  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
247  led_tm1637_tick(); // wait for next tick
248  gpio_set(GPIO(LED_TM1637_CLK_PORT), GPIO(LED_TM1637_CLK_PIN)); // put CLK high
249  led_tm1637_tick(); // wait for next tick
250  gpio_set(GPIO(LED_TM1637_DIO_PORT), GPIO(LED_TM1637_DIO_PIN)); // put DIO high
251  timer_disable_counter(TIM(LED_TM1637_TIMER)); // stop timer since it's not used anymore
252 
253  return to_return;
254 }
255 
256 bool led_tm1637_on(void)
257 {
258  uint8_t data[] = { 0x88+display_brightness }; // command to turn display on (use set brightness)
259  bool to_return = false; // result to return
260  if (led_tm1637_write(data,LENGTH(data))) { // send command
261  display_on = true; // remember display is on
262  to_return = true; // command succeeded
263  }
264  return to_return; // return result
265 }
266 
267 bool led_tm1637_off(void)
268 {
269  uint8_t data[] = { 0x80+display_brightness }; // command to turn display off (use set brightness)
270  if (led_tm1637_write(data,LENGTH(data))) { // send command
271  display_on = false; // remember display is off
272  return true; // command succeeded
273  }
274  return false; // return result
275 }
276 
278 {
279  display_brightness = brightness; // save brightness
280  if (display_on) { // adjust brightness if display is on
281  return led_tm1637_on(); // adjust brightness
282  } else {
283  return true; // command succeeded
284  }
285  return false;
286 }
287 
288 bool led_tm1637_number(uint16_t number)
289 {
290  uint8_t write_data[] = { 0x40 }; // command: write data, automatic address adding, normal
291  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
292 
293  if (led_tm1637_write(write_data,LENGTH(write_data)) && led_tm1637_write(data,LENGTH(data))) { // send commands
294  return true;
295  }
296  return false;
297 }
298 
299 bool led_tm1637_time(uint8_t hours, uint8_t minutes)
300 {
301  uint8_t write_data[] = { 0x40 }; // command: write data, automatic address adding, normal
302  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
303 
304  if (led_tm1637_write(write_data,LENGTH(write_data)) && led_tm1637_write(data,LENGTH(data))) { // send commands
305  return true;
306  }
307  return false;
308 }
309 
310 bool led_tm1637_text(char* text)
311 {
312  if (strlen(text)!=4) { // input text should have exactly 4 characters
313  return false;
314  }
315  for (uint8_t i=0; i<4; i++) { // input text should only contain printable character (8th bit is used for dots)
316  if ((text[i]&0x7f)<' ' || (text[i]&0x7f)>=' '+LENGTH(ascii_7segments)) {
317  return false;
318  }
319  }
320  uint8_t write_data[] = { 0x40 }; // command: write data, automatic address adding, normal
321  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
322 
323  if (led_tm1637_write(write_data,LENGTH(write_data)) && led_tm1637_write(data,LENGTH(data))) { // send commands
324  return true;
325  }
326  return false;
327 }
static const uint8_t ascii_7segments[]
ASCII characters encoded for the 7 segments digit block.
Definition: led_tm1637.c:68
bool led_tm1637_number(uint16_t number)
display number
Definition: led_tm1637.c:288
#define RCC_GPIO(x)
get RCC for GPIO based on GPIO identifier
Definition: global.h:105
static void led_tm1637_tick(void)
wait until clock tick (timer overflow) occurred
Definition: led_tm1637.c:189
library to communicate with a Titan Micro TM1637 IC attached to a 4-digit 7-segment (API) ...
static enum led_tm1637_brightness_t display_brightness
display brightness
Definition: led_tm1637.c:61
global definitions and methods (API)
#define GPIO(x)
get GPIO based on GPIO identifier
Definition: global.h:103
bool led_tm1637_brightness(enum led_tm1637_brightness_t brightness)
set display brightness
Definition: led_tm1637.c:277
#define LED_TM1637_CLK_PIN
pin for CLK signal
Definition: led_tm1637.c:49
#define RCC_TIM(x)
get RCC for timer based on TIM identifier
Definition: global.h:109
#define LED_TM1637_DIO_PORT
port for DIO signal
Definition: led_tm1637.c:50
static bool display_on
if display is on
Definition: led_tm1637.c:63
led_tm1637_brightness_t
display brightness levels
Definition: led_tm1637.h:26
#define LED_TM1637_CLK_PORT
port for CLK signal
Definition: led_tm1637.c:48
static bool led_tm1637_write(const uint8_t *data, size_t length)
write data on bus
Definition: led_tm1637.c:201
void led_tm1637_setup(void)
setup communication with TM1637 IC
Definition: led_tm1637.c:166
bool led_tm1637_off(void)
switch display off
Definition: led_tm1637.c:267
#define LENGTH(x)
get the length of an array
Definition: global.h:26
#define LED_TM1637_DIO_PIN
pin for DIO signal
Definition: led_tm1637.c:51
bool led_tm1637_time(uint8_t hours, uint8_t minutes)
display time
Definition: led_tm1637.c:299
bool led_tm1637_on(void)
switch display on
Definition: led_tm1637.c:256
#define TIM(x)
get TIM based on TIM identifier
Definition: global.h:107
#define LED_TM1637_TIMER
timer to create signal
Definition: led_tm1637.c:57
bool led_tm1637_text(char *text)
display text
Definition: led_tm1637.c:310