typedef gboolean (*packet_valid_t)(const uint8_t *buf);
/**
- * Try to find a valid packet in a serial data stream
+ * Try to find a valid packet in a serial data stream.
*
- * @param fd File descriptor of the serial port.
+ * @param serial Previously initialized serial port structure.
* @param buf Buffer containing the bytes to write.
* @param count Size of the buffer.
- * @param packet_size Size, in bytes, of a valid packet
- * @param is_valid callback that assesses whether the packet is valid or not
- * @param timeout_ms the timeout after which, if no packet is detected, to abort
- * scanning.
- * @param baudrate the baudrate of the serial port. This parameter is not
+ * @param packet_size Size, in bytes, of a valid packet.
+ * @param is_valid Callback that assesses whether the packet is valid or not.
+ * @param timeout_ms The timeout after which, if no packet is detected, to
+ * abort scanning.
+ * @param baudrate The baudrate of the serial port. This parameter is not
* critical, but it helps fine tune the serial port polling
- * delay
+ * delay.
*
- * @return SR_OK if a valid packet is found within he given timeout,
+ * @return SR_OK if a valid packet is found within the given timeout,
* SR_ERR upon failure.
*/
static int serial_stream_detect(struct sr_serial_dev_inst *serial,
uint8_t *buf, size_t *buflen,
- const size_t packet_size,
- packet_valid_t is_valid,
+ size_t packet_size, packet_valid_t is_valid,
uint64_t timeout_ms, int baudrate)
{
- uint64_t start;
- uint64_t time;
- uint64_t byte_delay_us;
- size_t ibuf, i;
+ uint64_t start, time, byte_delay_us;
+ size_t ibuf, i, maxlen;
int len;
- const size_t maxlen = *buflen;
- if(maxlen < (packet_size << 1) ) {
- sr_err("Buffer size must be at least twice the packet size");
+ maxlen = *buflen;
+
+ sr_dbg("Detecting packets on FD %d (timeout = %" PRIu64
+ "ms, baudrate = %d).", serial->fd, timeout_ms, baudrate);
+
+ if (maxlen < (packet_size / 2) ) {
+ sr_err("Buffer size must be at least twice the packet size.");
return SR_ERR;
}
timeout_ms *= 1000;
- /* Assume 8n1 transmission. That is 10 bits for every byte */
- byte_delay_us = 10000000 / baudrate;
+
+ /* Assume 8n1 transmission. That is 10 bits for every byte. */
+ byte_delay_us = 10 * (1000000 / baudrate);
start = g_get_monotonic_time();
i = ibuf = len = 0;
while (ibuf < maxlen) {
len = serial_read(serial, &buf[ibuf], 1);
- if (len > 0)
- ibuf+= len;
+ if (len > 0) {
+ ibuf += len;
+ } else if (len == 0) {
+ sr_spew("Error: Only read 0 bytes.");
+ } else {
+ /* Error reading byte, but continuing anyway. */
+ }
if ((ibuf - i) >= packet_size) {
- /* We have at least a packet's worth of data */
+ /* We have at least a packet's worth of data. */
if (is_valid(&buf[i])) {
- time = g_get_monotonic_time()-start;
+ time = g_get_monotonic_time() - start;
time /= 1000;
- sr_spew("Serial detection took %li ms", time);
+ sr_spew("Found valid %d-byte packet after "
+ "%" PRIu64 "ms.", (ibuf - i), time);
*buflen = ibuf;
return SR_OK;
+ } else {
+ sr_spew("Got %d bytes, but not a valid "
+ "packet.", (ibuf - i));
}
- /* Not a valid packet; continue searching */
+ /* Not a valid packet. Continue searching. */
i++;
}
if (g_get_monotonic_time() - start > timeout_ms) {
/* Timeout */
- sr_warn("Serial detection timeout");
+ sr_dbg("Detection timed out after %dms.", timeout_ms);
break;
}
g_usleep(byte_delay_us);
}
*buflen = ibuf;
- return SR_ERR;
+ sr_err("Didn't find a valid packet (read %d bytes).", *buflen);
+
+ return SR_ERR;
}
static GSList *lcd14_scan(const char *conn, const char *serialcomm)
if (!(serial = sr_serial_dev_inst_new(conn, serialcomm)))
return NULL;
- if (serial_open(serial, O_RDONLY|O_NONBLOCK) != SR_OK)
+ if (serial_open(serial, O_RDONLY | O_NONBLOCK) != SR_OK)
return NULL;
sr_info("Probing port %s readonly.", conn);
* the serial port or USB to serial adapter.
*/
dropped = len - FS9721_PACKET_SIZE;
- if (dropped > 2 * FS9721_PACKET_SIZE) {
-
- sr_warn("Had to drop too much data");
- }
+ if (dropped > 2 * FS9721_PACKET_SIZE)
+ sr_warn("Had to drop too much data.");
sr_info("Found device on port %s.", conn);
if (!(sdi = sr_dev_inst_new(0, SR_ST_INACTIVE, "TekPower",
"TP4000ZC", "")))
goto scan_cleanup;
+
if (!(devc = g_try_malloc0(sizeof(struct dev_context)))) {
sr_err("Device context malloc failed.");
goto scan_cleanup;
/* User-defined FS9721_LP3 flag 'c2c1_10' means temperature on this DMM. */
#define is_temperature info.is_c2c1_10
+static void log_dmm_packet(const uint8_t *buf)
+{
+ sr_dbg("DMM packet: %02x %02x %02x %02x %02x %02x %02x"
+ " %02x %02x %02x %02x %02x %02x %02x",
+ buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6],
+ buf[7], buf[8], buf[9], buf[10], buf[11], buf[12], buf[13]);
+}
+
/* Now see what the value means, and pass that on. */
static void fs9721_serial_handle_packet(const uint8_t *buf,
struct dev_context *devc)
struct sr_datafeed_analog *analog;
struct fs9721_info info;
+ log_dmm_packet(buf);
+
if (!(analog = g_try_malloc0(sizeof(struct sr_datafeed_analog)))) {
sr_err("Analog packet malloc failed.");
return;
}
if (devc->num_samples >= devc->limit_samples) {
+ sr_info("Requested number of samples reached, stopping.");
sdi->driver->dev_acquisition_stop(sdi, cb_data);
return TRUE;
}