int measure_updateRot(uint8_t *data, size_t len)
{
// Save the rot of current encoded data.
uint16_t rot;
rotating_init(&rot);
rotating_update(data, len, &rot);
LOG_INFO("Update rot in bkp[%d]\n", rot);
bkp_write(&rot, sizeof(uint16_t));
return 0;
}
int measure_isDataChage(uint8_t *data, size_t len)
{
uint16_t rot;
uint16_t prev_rot;
bkp_read(&prev_rot, sizeof(uint16_t));
rotating_init(&rot);
rotating_update(data, len, &rot);
LOG_INFO("Prev[%d] Now[%d]\n", prev_rot, rot);
if (rot == prev_rot)
return 0;
bkp_write(&rot, sizeof(uint16_t));
return 1;
}
/**
* Try to read a packet from the pocketBus.
* \return true if a packet is received, false otherwise.
*/
bool pocketbus_recv(struct PocketBusCtx *ctx, struct PocketMsg *msg)
{
int c;
/* Process incoming characters until buffer is not empty */
while ((c = kfile_getc(ctx->fd)) != EOF)
{
/* Look for STX char */
if (c == POCKETBUS_STX && !ctx->escape)
{
/* When an STX is found, inconditionally start a new packet */
if (ctx->sync)
kprintf("pocketBus double sync!\n");
ctx->sync = true;
ctx->len = 0;
rotating_init(&ctx->in_cks);
continue;
}
if (ctx->sync)
{
/* Handle escape mode */
if (c == POCKETBUS_ESC && !ctx->escape)
{
ctx->escape = true;
continue;
}
/* Handle message end */
if (c == POCKETBUS_ETX && !ctx->escape)
{
ctx->sync = false;
/* Check minimum size */
if (ctx->len < sizeof(PocketBusHdr) + sizeof(rotating_t))
{
kprintf("pocketBus short pkt!\n");
continue;
}
/* Remove checksum bytes from packet len */
ctx->len -= sizeof(rotating_t);
/* Compute checksum */
rotating_update(ctx->buf, ctx->len, &ctx->in_cks);
uint8_t cks_h = *(ctx->buf + ctx->len);
uint8_t cks_l = *(ctx->buf + ctx->len + 1);
rotating_t recv_cks = (cks_h << 8) | cks_l;
/* Checksum check */
if (recv_cks == ctx->in_cks)
{
PocketBusHdr *hdr = (PocketBusHdr *)ctx;
/* Check packet version */
if (hdr->ver == POCKETBUS_VER)
{
/* Packet received, set msg fields */
msg->payload = ctx->buf + sizeof(PocketBusHdr);
msg->addr = be16_to_cpu(hdr->addr);
msg->len = ctx->len - sizeof(PocketBusHdr);
msg->ctx = ctx;
return true;
}
else
{
kprintf("pocketBus version mismatch, here[%d], there[%d]\n", POCKETBUS_VER, hdr->ver);
continue;
}
}
else
{
kprintf("pocketBus cks error, here[%04X], there[%04X]\n", ctx->in_cks, recv_cks);
continue;
}
}
ctx->escape = false;
/* Check buffer overflow: simply ignore
received data and go to unsynced state. */
if (ctx->len >= CONFIG_POCKETBUS_BUFLEN)
{
kprintf("pocketBus buffer overflow\n");
ctx->sync = false;
continue;
}
/* Put received data in the buffer */
ctx->buf[ctx->len] = c;
ctx->len++;
}
}
/*
* Check stream status.
*/
if (kfile_error(ctx->fd))
{
LOG_ERR("fd status[%04X]\n", kfile_error(ctx->fd));
kfile_clearerr(ctx->fd);
}
return false;
}
