Command handing works!

The command handler can now receive a command, then it can run a
function / return some data based on it.

prosjekt.X/command-handler.c

@@ -1,9 +1,10 @@
 #include "command-handler.h"
 
-command_context_t parse_command(uint8_t *command, uint8_t command_len) {
+// Initialize empty, global command context
-  // Create the context
+volatile command_context_t context = {UNKNOWN_COMMAND, SRC_NONE, FAN_NONE,
-  command_context_t context;
+                                      CNF_NONE};
 
+void parse_command(uint8_t command[], uint8_t command_len) {
   ///////////////////////
   // Command selection //
   ///////////////////////
@@ -11,11 +12,12 @@ command_context_t parse_command(uint8_t *command, uint8_t command_len) {
   // Validate that we have a command
   if (command_len < 1) {
     context.command = UNKNOWN_COMMAND;
-    return context;
   }
 
+  uint8_t foo = command[0];
+
   // Figure out which command to run
-  switch (command[0]) {
+  switch (foo) {
   case 0x11: // Read config
     context.command = READ_CONFIG;
     break;
@@ -48,14 +50,14 @@ command_context_t parse_command(uint8_t *command, uint8_t command_len) {
 
   // Check if the command does not require a parameter. If it does not, return.
   if (context.command == READ_TERMPERATURE) {
-    return context;
+    return;
   }
 
   // Validate that we have a first parameter, else requirements for command are
   // not fulfilled. return unknown command.
   if (command_len < 2) {
     context.command = UNKNOWN_COMMAND;
-    return context;
+    return;
   }
 
   // Store the parameter
@@ -109,14 +111,14 @@ command_context_t parse_command(uint8_t *command, uint8_t command_len) {
   // Check if the command does not require a second parameter. If it does not,
   // return. Only config write requires a second parameter.
   if (context.command != WRITE_CONFIG) {
-    return context;
+    return;
   }
 
   // Validate that we have a first parameter, else requirements for command are
   // not fulfilled. return unknown command.
   if (command_len < 3) {
     context.command = UNKNOWN_COMMAND;
-    return context;
+    return;
   }
 
   // Store the parameter
@@ -124,8 +126,32 @@ command_context_t parse_command(uint8_t *command, uint8_t command_len) {
 
   // TODO: Handle the config parameters
 
-  // Return the context
+  // exit
-  return context;
+  return;
 }
 
-void route_command(command_context_t command);
+uint8_t route_command() {
+  switch (context.command) {
+  WRITE_CONFIG:
+    return WRITE_CONFIG;
+    break;
+  READ_CONFIG:
+    return READ_CONFIG;
+    break;
+  READ_VOLTAGE:
+    return READ_VOLTAGE;
+    break;
+  READ_TERMPERATURE:
+    return READ_TERMPERATURE;
+    break;
+  READ_FAN_SPEED:
+    return READ_FAN_SPEED;
+    break;
+  CLEAR_BULK_FAN_SPEED:
+    return CLEAR_BULK_FAN_SPEED;
+    break;
+  UNKNOWN_COMMAND:
+    return 0xFF;
+    break;
+  }
+}

prosjekt.X/command-handler.h

@@ -12,6 +12,7 @@
 extern "C" {
 #endif
 
+#include <avr/io.h>
 #include <stdint.h>
 #include <string.h>
 
@@ -59,10 +60,10 @@ typedef struct {
 } command_context_t;
 
 // Parses the input string and outputs one of the valid commands
-command_context_t parse_command(uint8_t *command, uint8_t command_len);
+void parse_command(uint8_t *command, uint8_t command_len);
 
 // Routes the provided command to the appropriate function to handle it
-void route_command(command_context_t command);
+uint8_t route_command();
 
 #ifdef __cplusplus
 }

prosjekt.X/i2c.c

@@ -1,9 +1,17 @@
 #include "i2c.h"
+#include "command-handler.h"
 
-// Basic I2C handling structure is heavily inspired by: https://github.com/microchip-pic-avr-examples/avr128db48-bare-metal-twi-mplab/blob/master/twi-client.X/peripherals/TWI/TWI_client.c
+// Basic I2C handling structure is heavily inspired by:
+// https://github.com/microchip-pic-avr-examples/avr128db48-bare-metal-twi-mplab/blob/master/twi-client.X/peripherals/TWI/TWI_client.c
 
-volatile uint8_t i2c_recv[I2C_RECV_BUF_SIZE]; // Arbitrary length array to hold the received data, longer than max expected command
+// We need to keep track of if the stop confition is in regards to a write or
-volatile uint8_t i2c_recv_len;
+// read request
+volatile bool last_action_write = false;
+
+volatile uint8_t i2c_recv[I2C_RECV_BUF_SIZE] = {
+    0}; // Arbitrary length array to hold the received
+        // data, longer than max expected command
+volatile uint8_t i2c_recv_len = 0;
 
 void init_i2c(void) {
   // Pin setup
@@ -44,23 +52,33 @@ void i2c_reset_recv() {
 }
 
 void i2c_write_handler(uint8_t data) {
+  last_action_write = true;
   i2c_recv[i2c_recv_len] = data;
   i2c_recv_len++;
 }
 
 void i2c_read_handler() {
-    printf("Master wanted to read.\n");
+  last_action_write = false;
+  TWI0.SDATA = route_command();
 }
 
 void i2c_stop_handler() {
-    // Reset counter and clear receive buffer
+  if (last_action_write) {
-    i2c_recv[i2c_recv_len] = '\0';
+    // Parse the received command data
-    printf("%s\n", i2c_recv);
+    parse_command(i2c_recv, i2c_recv_len);
+  } else {
+    // route_command();
+    ;
+  }
+  // Reset the buffer for future transmissions
   i2c_reset_recv();
 }
 
 // Address received
 ISR(TWI0_TWIS_vect) {
+  // Disable interrupts while handling I2C
+  cli();
+
   // Check for the data interrupt flag
   if (TWI0.SSTATUS & TWI_DIF_bm) {
     uint8_t data = 0;
@@ -74,7 +92,8 @@ ISR(TWI0_TWIS_vect) {
     } else {
       // Data read Master <- Slave
       i2c_read_handler();
-            data = TWI0.SDATA;
+      // data = TWI0.SDATA;
+      // TWI0.SDATA = 1;
     }
 
     // Acknowledge having received
@@ -94,4 +113,7 @@ ISR(TWI0_TWIS_vect) {
       TWI0.SCTRLB = TWI_ACKACT_ACK_gc | TWI_SCMD_RESPONSE_gc;
     }
   }
+
+  // Re-enable interrupts
+  sei();
 }

prosjekt.X/i2c.h

@@ -13,9 +13,11 @@ extern "C" {
 #endif
 
 // Include the IO for I2C
-#include <avr/io.h>
+#include "command-handler.h"
-#include <avr/interrupt.h>
 #include "uart.h"
+#include <avr/interrupt.h>
+#include <avr/io.h>
+#include <stdbool.h>
 #include <util/twi.h>
 
 // Received data info

prosjekt.X/main.c

@@ -11,17 +11,20 @@
 #include <stdlib.h>
 #include "uart.h"
 #include "i2c.h"
+#include "command-handler.h"
 #include <util/delay.h>
+#include <avr/io.h>
 
 int main() {    
     init_uart((uint16_t)9600);
     init_i2c();
     stdout = &USART_stream;
     
+    PORTB.DIRSET = PIN3_bm;
+    
     sei();
 
     while (1) {
-        printf("\n");
+        ;
-        _delay_ms(500);
     }
 }

prosjekt.X/nbproject/configurations.xml

@@ -149,6 +149,9 @@
         <property key="program-the-device-with-default-config-words" value="false"/>
         <property key="remove-unused-sections" value="true"/>
       </HI-TECH-LINK>
+      <Tool>
+        <property key="debugoptions.useswbreakpoints" value="true"/>
+      </Tool>
       <XC8-CO>
         <property key="coverage-enable" value=""/>
         <property key="stack-guidance" value="false"/>