static void chb_frame_read()
{
U8 i, len, data;
CHB_ENTER_CRIT();
RadioCS(TRUE);
/*Send frame read command and read the length.*/
SPID_write(CHB_SPI_CMD_FR);
len = SPID_write(0);
/*Check for correct frame length.*/
if ((len >= CHB_MIN_FRAME_LENGTH) && (len <= CHB_MAX_FRAME_LENGTH))
{
// check to see if there is room to write the frame in the buffer. if not, then drop it
if (len < (CHB_BUF_SZ - chb_buf_get_len()))
{
chb_buf_write(len);
for (i=0; i<len; i++)
{
data = SPID_write(0);
chb_buf_write(data);
}
//generate message received event here
//EVSYS.STROBE = 0x04; //generate event on channel 3
//generate interrupt on port E by toggling pin 2
//PORTE.OUTSET = PIN2_bm;
//PORTE.OUTCLR = PIN2_bm;
}
else
{
// we've overflowed the buffer. toss the data and do some housekeeping
pcb_t *pcb = chb_get_pcb();
//char buf[50];
// read out the data and throw it away
for (i=0; i<len; i++)
{
data = SPID_write(0);
}
// Increment the overflow stat
pcb->overflow++;
// grab the message from flash & print it out
//strcpy_P(buf, chb_err_overflow);
//printf(buf);
}
}
RadioCS(FALSE);
CHB_LEAVE_CRIT();
}
static void chb_frame_read()
{
U8 i, len, data;
CHB_ENTER_CRIT();
CHB_SPI_ENABLE();
/*Send frame read command and read the length.*/
chb_xfer_byte(CHB_SPI_CMD_FR);
len = chb_xfer_byte(0);
// check the length of the frame to make sure its within the correct size limits
if ((len >= CHB_MIN_FRAME_LENGTH) && (len <= CHB_MAX_FRAME_LENGTH))
{
// check to see if there is room to write the frame in the buffer. if not, then drop it
if (len < (CHB_BUF_SZ - chb_buf_get_len()))
{
chb_buf_write(len);
for (i=0; i<len; i++)
{
data = chb_xfer_byte(0);
chb_buf_write(data);
}
}
else
{
// this frame will overflow the buffer. toss the data and do some housekeeping
pcb_t *pcb = chb_get_pcb();
char buf[50];
// read out the data and throw it away
for (i=0; i<len; i++)
{
data = chb_xfer_byte(0);
}
// Increment the overflow stat, and print a message.
pcb->overflow++;
// grab the message from flash & print it out
strcpy_P(buf, chb_err_overflow);
Serial.print(buf);
}
}
CHB_SPI_DISABLE();
CHB_LEAVE_CRIT();
}
static void chb_frame_read()
{
U8 i, len, data;
// CHB_ENTER_CRIT();
CHB_SPI_ENABLE();
/*Send frame read command and read the length.*/
chb_xfer_byte(CHB_SPI_CMD_FR);
len = chb_xfer_byte(0);
/*Check for correct frame length.*/
if ((len >= CHB_MIN_FRAME_LENGTH) && (len <= CHB_MAX_FRAME_LENGTH))
{
// check to see if there is room to write the frame in the buffer. if not, then drop it
if (len < (CFG_CHIBI_BUFFERSIZE - chb_buf_get_len()))
{
chb_buf_write(len);
for (i=0; i<len; i++)
{
data = chb_xfer_byte(0);
chb_buf_write(data);
}
}
else
{
// we've overflowed the buffer. toss the data and do some housekeeping
chb_pcb_t *pcb = chb_get_pcb();
// read out the data and throw it away
for (i=0; i<len; i++)
{
data = chb_xfer_byte(0);
}
// Increment the overflow stat
pcb->overflow++;
// print the error message
printf(chb_err_overflow);
}
}
CHB_SPI_DISABLE();
CHB_LEAVE_CRIT();
}
U8 chb_read(chb_rx_data_t *rx)
{
U8 i, len, seq, *data_ptr;
data_ptr = rx->data;
// first byte is always len. check it to make sure
// we have a valid len byte.
if ((len = chb_buf_read()) > CHB_MAX_FRAME_LENGTH)
{
return 0;
}
*data_ptr++ = len;
// load the rest of the data into buffer
for (i=0; i<len; i++)
{
*data_ptr++ = chb_buf_read();
}
// we're using the buffer that's fed in as an argument as a temp
// buffer as well to save resources.
// we'll use it as temp storage to parse the frame. then move the frame
// down so that only the payload will be in the buffer.
// extract the sequence number
data_ptr = rx->data + 3; // location of sequence number
seq = *data_ptr;
// parse the buffer and extract the dest and src addresses
data_ptr = rx->data + 6; // location of dest addr
rx->dest_addr = *(U16 *)data_ptr;
data_ptr += sizeof(U16);
rx->src_addr = *(U16 *)data_ptr;
data_ptr += sizeof(U16);
// if the data in the rx buf is 0, then clear the rx_flag. otherwise, keep it raised
if (!chb_buf_get_len())
{
pcb.data_rcv = false;
}
#if (CHIBI_PROMISCUOUS)
// if we're in promiscuous mode, we don't want to do any duplicate rejection and we don't want to move the payload
// to the front of the buffer. We want to capture the full frame so just keep the frame intact and return the length.
return len;
#else
// duplicate frame check (dupe check). we want to remove frames that have been already been received since they
// are just retries.
// note: this dupe check only removes duplicate frames from the previous transfer. if another frame from a different
// node comes in between the dupes, then the dupe will show up as a received frame.
if ((seq == prev_seq) && (rx->src_addr == prev_src_addr))
{
// this is a duplicate frame from a retry. the remote node thinks we didn't receive
// it properly. discard.
return 0;
}
else
{
prev_seq = seq;
prev_src_addr = rx->src_addr;
}
// move the payload down to the beginning of the data buffer
memmove(rx->data, data_ptr, len - CHB_HDR_SZ);
// finally, return the len of the payload
return len - CHB_HDR_SZ - CHB_FCS_LEN;
#endif
}
