tabby/avr/recv.c

126 lines
2.6 KiB
C

#include <avr/io.h>
#include <avr/interrupt.h>
#include <avr/sleep.h>
#include <tabby/avr/printer.h>
#include <tabby/avr/uart.h>
#include <tabby/avr/link.h>
#include <tabby/avr.h>
static volatile uint16_t offset_header = 0,
offset_body = 0,
size_body = 0,
sum_calc = 0,
sum_footer = 0;
static volatile tabby_printer_response response = {
.device = TABBY_PRINTER_DEVICE_ID,
.status = TABBY_PRINTER_OK
};
/*
* SPI byte receipt interrupt vector
*/
ISR(SPI_STC_vect) {
uint8_t in = SPDR,
out = 0;
uart_putchar(in, NULL);
switch (offset_header) {
case 0: {
if (in == TABBY_PRINTER_SYNC_1) {
offset_header++;
offset_body = 0;
sum_calc = 0;
response.status = TABBY_PRINTER_OK;
}
break;
}
case 1: {
if (in == TABBY_PRINTER_SYNC_2) {
offset_header++;
} else {
offset_header = 0;
}
break;
}
case 2:
case 3: {
offset_header++;
sum_calc += in;
break;
}
case 4: {
size_body = in;
sum_calc += in;
offset_header++;
break;
}
case 5: {
size_body |= in << 8;
if (size_body > TABBY_PRINTER_PACKET_MAX_SIZE) {
offset_header = 0;
} else {
offset_header++;
}
sum_calc += in;
break;
}
default: {
if (offset_body < size_body) {
offset_body++;
sum_calc += in;
} else if (offset_body == size_body) {
offset_body++;
sum_footer = in;
} else if (offset_body == size_body + 1) {
offset_body++;
sum_footer |= in << 8;
if (sum_footer != sum_calc) {
response.status |= TABBY_PRINTER_SUM;
}
out = response.device;
} else if (offset_body == size_body + 2) {
offset_body++;
out = response.status;
} else if (offset_body == size_body + 3) {
offset_header = 0;
}
}
}
SPDR = out;
}
int main() {
uart_init();
tabby_avr_link_init_slave();
sei();
while (1) {
sleep_mode();
}
return 0;
}