first try getting both chips to work

cmdline/.gitignore

@@ -0,0 +1,2 @@
+read-temp
+*.o

cmdline/read-temp.c

@@ -89,7 +89,7 @@ int                 cnt, vid, pid;
     } else {
       int opcode, addr, value;
       int i=0;
-      sscanf(argv, "%i %i %i", &opcode, &addr, &value);
+      sscanf(argv[1], "%i %i %i", &opcode, &addr, &value);
       cnt = usb_control_msg(handle, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_ENDPOINT_IN, opcode, addr, value, buffer, sizeof(buffer), 5000);
       if(cnt < 0){
 	fprintf(stderr, "\nUSB error in iteration %d: %s\n", i, usb_strerror());
@@ -97,7 +97,7 @@ int                 cnt, vid, pid;
       rxValue = ((int)buffer[1] & 0xff) | (((int)buffer[0] & 0xff) << 8);
       rxIndex = ((int)buffer[3] & 0xff) | (((int)buffer[2] & 0xff) << 8);
       
-      fprintf(stderr, "request = 0x%04x", opcode);
+      fprintf(stderr, "request = 0x%04x\n", opcode);
       fprintf(stderr, "rxValue = 0x%04x value = 0x%04x\n", rxValue, addr);
       fprintf(stderr, "rxIndex = 0x%04x index = 0x%04x\n", rxIndex, value);
       

firmware/masterchip/main.c

@@ -44,6 +44,8 @@ void hardinit() {
   lcd_init(1);
   lcd_clrscr(1);
 
+  spi_init();
+
   sei();
 }
 

firmware/shared/spi.c

@@ -135,7 +135,7 @@ void __attribute__((always_inline)) spi_sla_handle_packet(){
 	}
 }
 
-ISR(SPI_vect){
+ISR(SPI_STC_vect){
     SPCR &= ~(_BV(SPIE)); //disable spi interrupts
     spi_sla_handle_packet(); 
     SPCR |= _BV(SPIE);

firmware/slavechip/main.c

@@ -13,8 +13,12 @@ void hardinit() {
   /* initializes the hardware */
 
   // enable softtimer isr
+  TCCR1A = _BV(WGM10);
+  TCCR1B = _BV(WGM12) | _BV(CS11); // clk/8 prescaler, 4kHz PWM-freq.
   TIMSK1 |= _BV(TOIE1);
 
+  spi_init();
+
   sei();
 }