From 78d6a233688058936d344c3e846d11dac8132949 Mon Sep 17 00:00:00 2001
From: Jan Michel <j.michel@gsi.de>
Date: Mon, 26 May 2014 17:01:03 +0200
Subject: [PATCH] firmware update with trailing line break

---
 Power/firmware/PowerSwitch.c | 124 ++++++++++++++++++-----------------
 1 file changed, 65 insertions(+), 59 deletions(-)

diff --git a/Power/firmware/PowerSwitch.c b/Power/firmware/PowerSwitch.c
index 74158b6..6a67b21 100755
--- a/Power/firmware/PowerSwitch.c
+++ b/Power/firmware/PowerSwitch.c
@@ -1,7 +1,7 @@
 #define F_CPU 6000000UL
 
 #include <avr/interrupt.h>
-// #include <util/delay.h>
+#include <util/delay.h>
 // #include <avr/sleep.h>
 // #include <stdint.h>
 #include <avr/io.h>
@@ -22,9 +22,10 @@
 //B2 Switch2 In 
 //B3 Reset   --
 
+//all commands end in \n
 // cc          -- channel address in hex 
 //Scc(0|1|/)   -- switch channel off/on/toggle
-//Scc?         -- read channel status
+//Scc?         -- read channel status - 2nd char: 'e' in case of overcurrent, 3rd char: enable 1/0
 //Ccc?         -- read current
 //Lccxxx       -- set current limit (hex)
 //Lcc?         -- read current limit
@@ -39,8 +40,8 @@ uint8_t  output_error = 0;
 uint16_t adc[2];
 
 uint8_t rxcnt = 0, txcnt = 0, txpoint = 0;
-uint8_t rxbuf[6];
-uint8_t txbuf[6];
+uint8_t rxbuf[7];
+uint8_t txbuf[7];
 uint16_t limit[2] = {0x0800,0x0800};
 
 uint8_t nib_to_hex(uint16_t in, uint8_t nib) {
@@ -73,7 +74,8 @@ void send_answer_hex(uint16_t v) {
   txbuf[1]=nib_to_hex(v,2);
   txbuf[2]=nib_to_hex(v,1);
   txbuf[3]=nib_to_hex(v,0);
-  STARTTX(4);
+  txbuf[4]='\n';
+  STARTTX(5);
   }
   
 void send_answer_chars(uint8_t a, uint8_t b, uint8_t c) {
@@ -81,7 +83,8 @@ void send_answer_chars(uint8_t a, uint8_t b, uint8_t c) {
   txbuf[1]=a;
   txbuf[2]=b;
   txbuf[3]=c;
-  STARTTX(4);
+  txbuf[4]='\n';
+  STARTTX(5);
   }
 
   
@@ -137,7 +140,7 @@ ISR(ADC_vect) {
 
 ISR(USART1_UDRE_vect) {
   UDR1 = txbuf[txpoint++];
-  if(--txcnt == 0) {  
+  if(--txcnt == 0 || txpoint > 7) {  
     txpoint = 0;
     UCSR1B &= ~(1<< UDRIE1);
     }
@@ -148,67 +151,68 @@ ISR(USART1_RX_vect) {
   if (rxcnt != 0 || (buf == 'S' || buf == 'A' || buf == 'L' || buf == 'C')) {
     rxbuf[rxcnt++] = buf;
     }
-  //Forward any incoming 4 letter answer  
-  if (rxcnt == 4) {
-    if (rxbuf[0] == 'A') {
-      rxcnt = 0;
-      memcpy ((uint8_t*)txbuf,(uint8_t*)rxbuf,4);
-      STARTTX(4);
-      }
-  //Four letter 'switch' command  
-    if (rxbuf[0] == 'S') {  
-      rxcnt = 0;
-      if (ISMYADDR()) {
-        rxbuf[2] -= '0';
-        if (rxbuf[3] != '?') {
-          switchoutput(rxbuf[2],rxbuf[3]-'0');
-          }
-        send_answer_chars('0', (output_error  & (1<<rxbuf[2]))?'e':'0', 
-                               (output_enable & (1<<rxbuf[2]))?'1':'0');      
-        }
-      else {
-        forward_msg(4);
+  //Forward any incoming 4 letter answer
+  if (buf == '\n' || buf == '\r') {
+    // if(rxcnt == 1 && rxbuf[0] == '\n') {
+      // txbuf[0] = '\n';
+      // STARTTX(1);
+      // }
+    if(rxcnt == 5) {
+      if (rxbuf[0] == 'A') {
+        memcpy ((uint8_t*)txbuf,(uint8_t*)rxbuf,4);
+        STARTTX(4);
         }
-      }
-  //Read current command
-    if (rxbuf[0] == 'C') { 
-      rxcnt = 0;
-      if (ISMYADDR()) {
-        if (rxbuf[3] == '?')
-          send_answer_hex(adc[rxbuf[2]-'0']);
+    //Four letter 'switch' command  
+      if (rxbuf[0] == 'S') {  
+        if (ISMYADDR()) {
+          rxbuf[2] -= '0';
+          if (rxbuf[3] != '?') {
+            switchoutput(rxbuf[2],rxbuf[3]-'0');
+            }
+          send_answer_chars('0', (output_error  & (1<<rxbuf[2]))?'e':'0', 
+                                 (output_enable & (1<<rxbuf[2]))?'1':'0');      
+          }
+        else {
+          forward_msg(5);
+          }
         }
-      else {
-        forward_msg(4);
+    //Read current command
+      if (rxbuf[0] == 'C') { 
+        if (ISMYADDR()) {
+          if (rxbuf[3] == '?')
+            send_answer_hex(adc[rxbuf[2]-'0']);
+          }
+        else {
+          forward_msg(5);
+          }
         }
+    //Read current limit    
+      if (rxbuf[0] == 'L' && rxbuf[3] == '?') {
+        if (ISMYADDR()) {
+          send_answer_hex(limit[rxbuf[2]-'0']);      
+          }
+        else {
+          forward_msg(5);
+          }
+        } 
       }
-  //Read current limit    
-    if (rxbuf[0] == 'L' && rxbuf[3] == '?') {
-      rxcnt = 0;
+  //Set current limit
+    if (rxcnt == 7 && rxbuf[0] == 'L') {
       if (ISMYADDR()) {
-        send_answer_hex(limit[rxbuf[2]-'0']);      
+        rxbuf[2] -= '0';
+        if(rxbuf[3] != '?') {
+          uint16_t lim = hex_to_int(rxbuf[3])*256 + hex_to_int(rxbuf[4])*16 + hex_to_int(rxbuf[5]);
+          limit[rxbuf[2]] = lim;
+          }
+        send_answer_hex(limit[rxbuf[2]]);   
         }
       else {
-        forward_msg(4);
+        forward_msg(7);
         }
       } 
-    }
-  //Set current limit
-  if (rxcnt == 6 && rxbuf[0] == 'L') {
-    rxcnt = 0;
-    if (ISMYADDR()) {
-      rxbuf[2] -= '0';
-      if(rxbuf[3] != '?') {
-        uint16_t lim = hex_to_int(rxbuf[3])*256 + hex_to_int(rxbuf[4])*16 + hex_to_int(rxbuf[5]);
-        limit[rxbuf[2]] = lim;
-        }
-      send_answer_hex(limit[rxbuf[2]]);   
-      }
-    else {
-      forward_msg(6);
-      }
-    }   
+    }      
     
-  if (rxcnt >= 6) { rxcnt = 0; }  
+  if (rxcnt >= 7 || buf == '\n' || buf == '\r') { rxcnt = 0; }  
     
 } 
 
@@ -238,10 +242,12 @@ __attribute__((naked)) int main(void) {
   DIDR0  = (1<<ADC1D) | (1<< ADC7D); //disable digital inputs
   
   UCSR1A = (1 << U2X1);
-  UCSR1B = (1 << RXCIE1) | (0 << TXCIE1) | (1 << RXEN1) | (1 << TXEN1);
+  UCSR1B = (1 << RXCIE1) | (0 << TXCIE1) | (0 << RXEN1) | (1 << TXEN1);
   UCSR1C = (3 << UCSZ10); //8 Bit
   UBRR1  = 0x26; //19200
   
+  _delay_ms(100);
+  UCSR1B |= (1 << RXEN1);
   sei();  
   while(1) {
     
-- 
2.43.0