added 3 & 4 digit voltmeter schematics

voltmeters/src/5-digit/interrupts.c

@@ -21,6 +21,7 @@
 
 #include "stm8l.h"
 #include "interrupts.h"
+#include "soft_i2c.h"
 
 // Top Level Interrupt
 INTERRUPT_HANDLER(TLI_IRQHandler, 0){}
@@ -85,26 +86,15 @@ INTERRUPT_HANDLER(TIM5_CAP_COM_IRQHandler, 14){}
 INTERRUPT_HANDLER(TIM2_UPD_OVF_BRK_IRQHandler, 13){}
 
 // Timer2 Capture/Compare Interrupt
-// store the current counter value and wait for next pulse
+// process soft I2C
 INTERRUPT_HANDLER(TIM2_CAP_COM_IRQHandler, 14){
-	/*
-	TIM2_CR1 = 0; // stop timer
-	if(TIM2_SR2){ // overcapture: noice etc.
-		TIM2_SR2 = 0;
-		TIM2_SR1 = 0;
-		ZW_off();
-		return;
+	if(TIM2_SR1 & TIM_SR1_UIF){
+		TIM2_SR1 &= ~TIM_SR1_UIF; // take off flag
+		tick_counter++;
+		process_soft_I2C();
 	}
-	ZW_catch_bit();
-	TIM2_SR1 = 0;
-	TIM2_CNTRH = 0;
-	TIM2_CNTRL = 0;
-	*/
 }
-/*
-	TIM2_CCMR2 = 1; // IC2 is mapped on TI2FP2
-	TIM2_CCMR1 = 2; // IC1 is mapped on TI2FP1
-*/
+
 #endif // STM8S903
 
 #if defined (STM8S208) || defined(STM8S207) || defined(STM8S007) || defined(STM8S105) || \

voltmeters/src/5-digit/main.c

@@ -22,6 +22,7 @@
 #include "main.h"
 #include "interrupts.h"
 #include "led.h"
+#include "soft_i2c.h"
 
 U32 Global_time = 0L; // global time in ms
 eeprom_data *saved_data = (eeprom_data*)EEPROM_START_ADDR;
@@ -66,7 +67,8 @@ void eeprom_default_setup(){
 int main() {
 	U32 T_LED = 0L;  // time of last digit update
 	U32 T_time = 0L; // timer
-
+	long voltage = 0L;
+	U8 cntr = 0;
 	// Configure clocking
 	CLK_CKDIVR = 0; // F_HSI = 16MHz, f_CPU = 16MHz
 	// Configure pins
@@ -103,18 +105,46 @@ int main() {
 	TIM2_IER = TIM_IER_CC2IE;
 	*/
 	eeprom_default_setup();
+	soft_I2C_setup();
+	soft_I2C_write_config(0xd0, 0x1c); // write configuration
 	// enable all interrupts
 	enableInterrupts();
 	set_display_buf("-----"); // on init show -----
 	// Loop
 	do {
-		if(((unsigned int)(Global_time - T_time) > 1000) || (T_time > Global_time)){ // once per 3 seconds we start measurement
+		// onse per 300ms refresh displayed value
+		if(((unsigned int)(Global_time - T_time) > 300) || (T_time > Global_time)){
 			T_time = Global_time;
-			display_long(testtimer++,0);
+			switch (soft_I2C_state){
+				case SOFT_I2C_NO_DEVICE:
+					set_display_buf(" EEE "); // error
+				break;
+				default: // refresh data
+					voltage /= cntr;
+					display_long(voltage, 1);
+					cntr = 0;
+					voltage = 0;
+			}
+
+			//display_long(testtimer++,0);
 		}
 		if((U8)(Global_time - T_LED) > LED_delay){
+			if(soft_I2C_state == SOFT_I2C_DATA_READ_OK){
+				if((readed_data & 1<<7) == 0){ // !RDY == 0
+					readed_data >>= 8;
+					// prepare data for rounded output
+					voltage += (long)(readed_data & 0x3ffff);
+					cntr++;
+				}
+			}
 			T_LED = Global_time;
 			show_next_digit();
+			// refresh data
+			if(soft_I2C_state == SOFT_I2C_NO_DEVICE){ // try to repeat writing config after an error
+				soft_I2C_write_config(0xd0, 0x1c);
+			}else{
+				soft_I2C_read4bytes(0xd0);
+			}
 		}
 	} while(1);
 }

voltmeters/src/5-digit/main.h

@@ -18,6 +18,9 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  * MA 02110-1301, USA.
  */
+#pragma once
+#ifndef __MAIN_H__
+#define __MAIN_H__
 
 #include "stm8l.h"
 
@@ -31,3 +34,7 @@ typedef struct{
 	U32 max_ADU;
 }eeprom_data;
 
+#define CONCAT(a,b)		a##_##b
+#define PORT(a,b)		CONCAT(a,b)
+
+#endif // __MAIN_H__

voltmeters/src/5-digit/soft_i2c.c

@@ -0,0 +1,203 @@
+/*
+ * soft_i2c.c - functions emulating I2C
+ *
+ * Copyright 2015 Edward V. Emelianoff <eddy@sao.ru>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ */
+
+#include "soft_i2c.h"
+#include "main.h"
+
+// data to transmit: MSB is devaddr, LSB is configuration byte
+U16 transmit_cmd;
+// == 0 when transmission is in progress
+U8 transmission_over = 1;
+// tick counter: two ticks for one bit writting and two ticks for empty
+U8 tick_counter;
+soft_I2C_errors soft_I2C_state = SOFT_I2C_BUSY;
+
+U16 tr_mask = 0; // mask that would be &`ded with transmit_cmd
+U32 readed_data; // data readed by I2C
+U32 rd_counter = 0; // counter of readed bits == 64 in start of reading; decrements in each readed bit
+
+/*
+ ********************* GPIO (page 111) ********************
+ * Px_ODR - Output data register bits
+ * Px_IDR - Pin input values
+ * Px_DDR - Data direction bits (1 - output)
+ * Px_CR1 - DDR=0: 0 - floating, 1 - pull-up input; DDR=1: 0 - pseudo-open-drain, 1 - push-pull output [not for "T"]
+ * Px_CR2 - DDR=0: 0/1 - EXTI disabled/enabled; DDR=1: 0/1 - 2/10MHz
+ *
+ */
+/**
+ * configure pins: SDA - open-drain output
+ * SCL - push/pull
+ * configure timer2 as CLK (default speed is 100kHz)
+ */
+void soft_I2C_setup(){
+	PORT(I2C_SCL_PORT, DDR) |= I2C_SCL_PIN;
+	PORT(I2C_SDA_PORT, DDR) |= I2C_SDA_PIN;
+	PORT(I2C_SDA_PORT, CR1) |= I2C_SDA_PIN;
+	// Configure timer 2 to generate signals for CLK
+	TIM2_PSCR = 0; // 16MHz
+	TIM2_IER = TIM_IER_UIE; // update interrupt enable
+	TIM2_CR1 |= TIM_CR1_APRE | TIM_CR1_URS; // auto reload + interrupt on overflow
+	TIM2_ARRH = 0; // set 2.5ms period (100kHz)
+	TIM2_ARRL = 10;
+}
+
+/**
+ * Set speed of soft I2C
+ * @param Pulse_len - period (in us) of one pulse
+ */
+void soft_I2C_set_speed(U16 Pulse_len){
+	Pulse_len << 2; // multiply on 4 as we have four pulses for each bit, each pulse is 62.5ns
+	TIM2_ARRH = Pulse_len >> 8; // set speed
+	TIM2_ARRL = Pulse_len & 0xff;
+}
+
+/*
+ * The data transmission runs only when SCL==1 & SDA have constant level,
+ * otherwice, if SCL==1 and SDA changes, this is: START(1->0) or STOP(0->1)
+ */
+void i2c_transmit(){
+	soft_I2C_state = SOFT_I2C_BUSY;
+	transmission_over = 0;
+	tick_counter = 0;
+	rd_counter = 0;
+	readed_data = 0;
+	TIM2_CR1 |= TIM_CR1_CEN; // turn on timer
+}
+
+/**
+ * write a byte to config register of device dev
+ * @param dev  - device address
+ * @param conf - configuration byte data
+ */
+U8 soft_I2C_write_config(U8 dev, U8 conf){
+	if(!transmission_over || (TIM2_CR1&TIM_CR1_CEN)) return SOFT_I2C_BUSY;
+	dev &= 0xfe; // make sure that r/!w clear
+	transmit_cmd = dev<<8 || conf;
+	i2c_transmit();
+	return SOFT_I2C_OK;
+}
+
+/**
+ * prepare to read 4 bytes of data
+ * @param dev - device address
+ */
+U8 soft_I2C_read4bytes(U8 dev){
+	if(!transmission_over || (TIM2_CR1&TIM_CR1_CEN)) return SOFT_I2C_BUSY;
+	dev |= 1; // make sure that r/!w is set
+	transmit_cmd = dev<<8;
+	i2c_transmit();
+	return SOFT_I2C_OK;
+}
+
+void process_soft_I2C(){
+	U8 nbit, bitinbyte, tick; // bit number
+	if(transmission_over){
+		TIM2_CR1 &= ~TIM_CR1_CEN; // turn off timer
+		// return line to NOT BUSY state
+		PORT(I2C_SCL_PORT, ODR) |= I2C_SCL_PIN;
+		PORT(I2C_SDA_PORT, ODR) |= I2C_SDA_PIN;
+		return;
+	}
+	nbit = tick_counter >> 2; // divide by 4
+	if(nbit == 0){ // start
+		switch (tick_counter){
+			case 1: // 2nd half of start pulse
+				PORT(I2C_SDA_PORT, ODR) &= ~I2C_SDA_PIN; // clear SDA - Start bit
+			break;
+			case 3: // turn to zero both SCL & SDA
+				PORT(I2C_SCL_PORT, ODR) &= ~I2C_SCL_PIN; // clear SCL, SDA is already cleared
+			break;
+			default: // keep current state
+				;
+		}
+		tr_mask = 1<<15; // MSB first
+		return;
+	}
+	bitinbyte = (nbit-1) % 9; // bit counter in each byte
+	tick = tick_counter % 4; // this is a tick inside bit
+	// now prepare data
+	if(bitinbyte == 8){ // ACK
+		switch (tick){
+			case 0: // ACK bit
+				if(nbit == 9) // check line - set ACK to 1
+					PORT(I2C_SDA_PORT, ODR) |= I2C_SDA_PIN;
+				else // set ACK to 0 - we are in reading mode
+					PORT(I2C_SDA_PORT, ODR) &= ~I2C_SDA_PIN;
+			break;
+			case 1: // check ACK
+				if(nbit == 9 && (PORT(I2C_SDA_PORT, ODR) & I2C_SDA_PIN)){ // not zero - very bad
+					transmission_over = 1;
+					soft_I2C_state = SOFT_I2C_NO_DEVICE;
+					return;
+				}
+			break;
+			default: // do nothing
+				;
+		}
+	}else{//data transmision; or STOP
+		if((tr_mask == 0) && (rd_counter == 0)){ // data sent, now we should send STOP in write mode
+			// in reading mode - send STOP only when rd_mask == 0
+			if(tick == 1){ // STOP is 0->1 when CLK is high
+				PORT(I2C_SDA_PORT, ODR) |= I2C_SDA_PIN;
+				transmission_over = 1;
+				if(transmit_cmd & 1<<8) // reading mode
+					soft_I2C_state = SOFT_I2C_DATA_READ_OK;
+				else // writting mode
+					soft_I2C_state = SOFT_I2C_DATA_SEND_OK;
+			}
+		}
+		if(tick == 0){ // start of bit
+			if(tr_mask){ // transmission
+				if(transmit_cmd & tr_mask){ // send one
+					PORT(I2C_SDA_PORT, ODR) |= I2C_SDA_PIN;
+				} // if we need to send 0, we already have data in zero state
+				tr_mask >>= 1;
+				// stop transmission after first byte in read mode
+				if((tr_mask == 1<<7) && (transmit_cmd & 1<<8)){ // go to reading mode
+					tr_mask = 0;
+					rd_counter = 64;
+				}
+			}
+		}else if(tick == 1){ // capture readed data
+			if((tr_mask == 0) && (transmit_cmd & 1<<8)){ // we are waiting for data
+				rd_counter--;
+				readed_data <<= 1;
+				if(PORT(I2C_SDA_PORT, IDR) & I2C_SDA_PIN) // read 1
+					readed_data |= 1;
+			}
+		}
+	}
+	// and at last - set level of SCL
+	switch (tick){ // set proper value of SCL
+		case 0: // high pulse
+			PORT(I2C_SCL_PORT, ODR) |= I2C_SCL_PIN;
+		break;
+		case 3: // low pulse & clear SDA
+			PORT(I2C_SDA_PORT, ODR) &= ~I2C_SDA_PIN;
+			PORT(I2C_SCL_PORT, ODR) &= ~I2C_SCL_PIN;
+		break;
+		default: // do nothing
+			;
+	}
+
+}
+

voltmeters/src/5-digit/soft_i2c.h

@@ -0,0 +1,52 @@
+/*
+ * soft_i2c.h
+ *
+ * Copyright 2015 Edward V. Emelianoff <eddy@sao.ru>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ */
+
+#pragma once
+#ifndef __SOFT_I2C_H__
+#define __SOFT_I2C_H__
+
+#include "stm8l.h"
+
+// SDA - PC7, SCL - PD1
+#define I2C_SDA_PORT	PC
+#define I2C_SDA_PIN		GPIO_PIN7
+#define I2C_SCL_PORT	PD
+#define I2C_SCL_PIN		GPIO_PIN1
+
+typedef enum{
+	 SOFT_I2C_OK            // all OK
+	,SOFT_I2C_BUSY          // previous transmission is active
+	,SOFT_I2C_NO_DEVICE     // no device found
+	,SOFT_I2C_DATA_SEND_OK  // data transmitted without errors
+	,SOFT_I2C_DATA_READ_OK  // data readed without errors
+} soft_I2C_errors;
+
+extern soft_I2C_errors soft_I2C_state;
+extern U32 readed_data;
+extern U8 tick_counter;
+
+void soft_I2C_setup();
+void soft_I2C_set_speed(U16 Pulse_len);
+void process_soft_I2C();
+U8 soft_I2C_write_config(U8 dev, U8 conf);
+U8 soft_I2C_read4bytes(U8 dev);
+
+#endif // __SOFT_I2C_H__