From 1ee4d3bd9057dce6b0750de8f0f3af575d8c1560 Mon Sep 17 00:00:00 2001
From: Jan Michel <j.michel@gsi.de>
Date: Fri, 7 Feb 2020 10:26:35 +0100
Subject: [PATCH] add better startup and calibration. Manual calibration is
 available to compensate for offsets after relays switched on

---
 atmega32u4/power48/main.c | 54 +++++++++++++++++++++++++++------------
 1 file changed, 37 insertions(+), 17 deletions(-)

diff --git a/atmega32u4/power48/main.c b/atmega32u4/power48/main.c
index 73c90ce..047007b 100644
--- a/atmega32u4/power48/main.c
+++ b/atmega32u4/power48/main.c
@@ -7,7 +7,7 @@
 #include <string.h>
 #include <usb_serial.h>
 
-#define FIRMWARE_VERSION 0x011
+#define FIRMWARE_VERSION 0x012
 
 
 //Channels 0 1 2 3: PD4, PB6, PF6, PF1
@@ -23,6 +23,8 @@
 //Scc?         -- read channel status - 2nd char: 'e' in case of overcurrent, 3rd char: enable 1/0
 //Ccc?         -- read current
 //Dcc?         -- read averaged current
+//Ecc?         -- read raw ADC value
+//Bcc?         -- read ADC channel offset
 //Lccxxx       -- set current limit (hex)
 //Lcc?         -- read current limit
 //Axxx         -- answer - three hex digits or chars
@@ -30,6 +32,7 @@
 //Pcc(0|1)     -- Do a automatic power cycle (2 seconds long)
 //Rcc?         -- read ADC measurement of internal 1.1V reference (one register)
 //Icc?         -- Firmware Info
+//F001         -- Force another calibration with relais 
 
 #define ISMYADDR() (rxbuf[1] == '0' && (rxbuf[2] == '0' || rxbuf[2] == '1' || rxbuf[2] == '2' || rxbuf[2] == '3') )
 
@@ -44,8 +47,10 @@ uint8_t  output_enable = 0x3;
 uint8_t  output_error = 0;
 uint8_t  adc_enable = 1;
 uint8_t  calibphase = 1;
+uint8_t  forcecalib = 0;
 uint16_t adc_offset[4] = {0,0,0,0};
 uint16_t adc[4];
+uint16_t raw[4];
 uint16_t avgadc[4] = {0,0,0,0};
 uint8_t  countdown[4] = {0,0,0,0};
 uint16_t adc_reference = 0;
@@ -141,7 +146,7 @@ void switchoutput(uint8_t chan, int8_t to) {
 
   if(to >= -1) {settings_changed |= 16;}
   
-  if((output_enable & (1<< chan))) {  // && !(output_error & (1<< chan))
+  if((output_enable & (1<< chan)) ) {  // && !(output_error & (1<< chan))
     switch (chan) {
       case 0 : PORTD |= (1<<4);   break;
       case 1 : PORTB |= (1<<6);   break;
@@ -173,13 +178,17 @@ void correct_adc(uint8_t channel) {
       }
     if (adc[channel] > 0x300)
       adc[channel] = 0;
-    if(adc_offset[channel] > adc[channel] ) {
+    if(adc_offset[channel]+0x30 > adc[channel] ) {
       adc[channel] = adc_offset[channel] - adc[channel];
       adc[channel] *= 25;
       }
     else {
       adc[channel] = 0;
       }
+    if(channel == 3 && forcecalib == 1) {
+      calibphase = 1;
+      forcecalib = 0;
+      }  
     }
     
     
@@ -224,9 +233,12 @@ ISR(ADC_vect) {
     case 2:
     case 3:
       adc[channel] = ADC; 
+      raw[channel] = adc[channel];
       correct_adc(channel);
       avgadc[channel] -= avgadc[channel]/8;
-      avgadc[channel] += adc[channel];
+      if(adc[channel] < 0x800) {
+        avgadc[channel] += adc[channel];
+        }
       if(limit[channel]*8<avgadc[channel]) {
         output_error |= (1<<channel);
         switchoutput(channel,-2);
@@ -246,8 +258,8 @@ ISR(ADC_vect) {
   }
 
 void getdata(uint8_t buf) {
-  if (rxcnt != 0 || (buf == 'S' || buf == 'A' || buf == 'L' || buf == 'C' || buf == 'I'
-                                || buf == 'D' || buf == 'O' || buf == 'P' || buf == 'R')) {
+  if (rxcnt != 0 || (buf == 'S' || buf == 'A' || buf == 'L' || buf == 'C' || buf == 'I' || buf == 'B' || buf == 'E'
+                                || buf == 'D' || buf == 'O' || buf == 'P' || buf == 'R' || buf == 'F')) {
     rxbuf[rxcnt++] = buf;
     }
   if (buf == '\n' || buf == '\r') {
@@ -282,16 +294,24 @@ void getdata(uint8_t buf) {
         
 //Read current command
       if (rxbuf[0] == 'C' && rxbuf[3] == '?' && is_my_address(5)) { 
-        if(adc_enable == 3) {  send_answer_hex(adc[rxbuf[2]]+0x800);  }
-        else                {  send_answer_hex(adc[rxbuf[2]]);        }
+        send_answer_hex(adc[rxbuf[2]]);
         }
         
 //Read average current command
       if (rxbuf[0] == 'D' && rxbuf[3] == '?' && is_my_address(5)) {
-        if(adc_enable == 3) {  send_answer_hex(avgadc[rxbuf[2]]/8+0x800);  }
-        else                {  send_answer_hex(adc_offset[rxbuf[2]]);        } //avgadc[rxbuf[2]]/8
+        send_answer_hex(avgadc[rxbuf[2]]/8);
+        }
+
+//Read offset command
+      if (rxbuf[0] == 'B' && rxbuf[3] == '?' && is_my_address(5)) {
+        send_answer_hex(adc_offset[rxbuf[2]]);         //avgadc[rxbuf[2]]/8
         }
 
+//Read raw command
+      if (rxbuf[0] == 'E' && rxbuf[3] == '?' && is_my_address(5)) {
+        send_answer_hex(raw[rxbuf[2]]);    
+        }        
+        
 //Read firmware info
       if (rxbuf[0] == 'I' && rxbuf[3] == '?' && is_my_address(5)) {
         send_answer_hex(FIRMWARE_VERSION);
@@ -316,7 +336,11 @@ void getdata(uint8_t buf) {
         send_answer_hex(adc_reference);      
         } 
       }
-      
+//Redo calibration without changing relais 
+      if (rxbuf[0] == 'F' && rxbuf[3] == '1' && is_my_address(5)) {
+        forcecalib = 1;
+        } 
+       
       
 //Set current limit
     if (rxcnt == 7 && rxbuf[0] == 'L' && is_my_address(7)) {
@@ -423,11 +447,7 @@ __attribute__((naked)) int main(void) {
   limit[3]  |= eeprom_read_byte((uint8_t*)0x26);  
   adc_enable = eeprom_read_byte((uint8_t*)0x28);
   output_enable = eeprom_read_byte((uint8_t*)0x29);
-  switchoutput(0,-3);
-  switchoutput(1,-3);
-  switchoutput(2,-3);
-  switchoutput(3,-3);
-  
+    
   //Timer0 at ~122 Hz overflow for ADC control and buttons
   TCCR0B = (4 << CS00);
   TIMSK0 = (1 << TOIE0); //Overflow interrupt`
@@ -438,7 +458,7 @@ __attribute__((naked)) int main(void) {
   UCSR1B = (1 << RXCIE1) | (0 << TXCIE1) | (0 << RXEN1) | (1 << TXEN1);
   UCSR1C = (3 << UCSZ10); //8 Bit
   UBRR1  = 0x10; //57600
-  _delay_ms(10);
+  _delay_ms(100);
   UCSR1B |= (1 << RXEN1);
   
   ADMUX  = (3 << REFS0); //reference 2.56V internal
-- 
2.43.0