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#include <global.h>
#include "microcobs.h"
#include "crc32.h"
struct __attribute__((packed)) ll_pkt_trailer {
uint32_t crc32;
};
struct __attribute__((packed)) req_pkt {
uint32_t req_seq;
struct ll_pkt_trailer trailer;
};
struct __attribute__((packed)) res_pkt {
uint32_t req_seq;
uint32_t res_seq;
struct ll_pkt_trailer trailer;
};
struct tx_state {
uint8_t *tx_char;
int remaining_bytes;
};
static crc32_t pkt_crc(void *pkt, struct ll_pkt_trailer *trailer);
crc32_t pkt_crc(void *pkt, struct ll_pkt_trailer *trailer) {
crc32_t crc = crc32_reset();
for (uint8_t *in = (uint8_t *)pkt; in < (uint8_t *)trailer; in++) {
crc = crc32_update(crc, *in);
}
return crc32_finalize(crc);
}
static void packetize(void *pkt, struct ll_pkt_trailer *trailer);
void packetize(void *pkt, struct ll_pkt_trailer *trailer) {
trailer->crc32 = pkt_crc(pkt, trailer);
}
int main(void) {
RCC->AHBENR |= RCC_AHBENR_GPIOAEN;
RCC->APB2ENR |= RCC_APB2ENR_USART1EN;
GPIOA->MODER |= (2 << GPIO_MODER_MODER9_Pos) | (2 << GPIO_MODER_MODER10_Pos);
GPIOA->AFR[1] = (7 << (9-8)*4) | (7 << (10-8)*4);
SystemCoreClockUpdate();
int apb2_clock = SystemCoreClock / APB2_PRESC;
int baudrate = 115200;
USART1->CR1 = USART_CR1_TE | USART_CR1_RE;
USART1->BRR = (apb2_clock + baudrate/2) / baudrate;
USART1->CR2 |= USART_CR2_RXINV; //| USART_CR2_TXINV;
USART1->CR1 |= USART_CR1_UE;
int req_seq = 0;
int res_seq = 0;
struct req_pkt req_buf = { 0 };
struct tx_state tx_st = { 0 };
struct res_pkt res_buf = { 0 };
uint8_t rx_buf[512];
uint8_t tx_buf[512];
size_t rx_char = 0;
unsigned int rx_overrun = 0;
unsigned int rx_cobs_error = 0;
unsigned int rx_framing_error = 0;
unsigned int rx_crc_error = 0;
USART1->TDR = 0; /* Kick off transmission */
int i = 0;
while (23) {
if (tx_st.remaining_bytes == 0) {
if (i > 100) {
res_buf.req_seq = req_seq;
res_buf.res_seq = res_seq;
res_seq += 1;
packetize(&res_buf, &res_buf.trailer);
tx_st.tx_char = tx_buf;
tx_st.remaining_bytes = cobs_encode((uint8_t *)&res_buf, sizeof(res_buf), tx_buf, sizeof(tx_buf));;
/*
for (int k=0; k < 8; k++)
tx_buf[k] = 255-k;
for (int k=0; k < 8; k++)
tx_buf[8+k] = (k + 1) % 8;
tx_st.remaining_bytes = 16;
*/
i = 0;
} else {
i++;
}
}
if (USART1->ISR & USART_ISR_TXE && tx_st.remaining_bytes > 0) {
USART1->TDR = *(tx_st.tx_char);
tx_st.tx_char += 1;
tx_st.remaining_bytes -= 1;
}
if (USART1->ISR & USART_ISR_ORE)
USART1->ICR = USART_ICR_ORECF;
if (USART1->ISR & USART_ISR_NE)
USART1->ICR = USART_ICR_NCF;
if (USART1->ISR & USART_ISR_FE)
USART1->ICR = USART_ICR_FECF;
if (USART1->ISR & USART_ISR_RXNE) {
uint8_t c = USART1->RDR;
if (!c) {
if (rx_char < sizeof(rx_buf)) {
int rc = cobs_decode(rx_buf, rx_char, (uint8_t *)&req_buf, sizeof(req_buf));
if (rc < 0) {
rx_cobs_error += 1;
} else {
if (rc == sizeof(req_buf)) {
crc32_t check_crc = pkt_crc(&req_buf, &req_buf.trailer);
if (check_crc != req_buf.trailer.crc32 || check_crc == 0 || check_crc == -1) {
rx_crc_error += 1;
} else {
req_seq = req_buf.req_seq;
}
} else {
rx_framing_error += 1;
}
}
}
rx_char = 0;
} else {
if (rx_char < sizeof(rx_buf)) {
rx_buf[rx_char] = c;
rx_char += 1;
} else {
rx_overrun += 1;
}
}
}
}
}
void __libc_init_array (void) __attribute__((weak));
void __libc_init_array ()
{
}
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