libsigrok/hardware/radioshack-dmm/protocol.c

116 lines
2.9 KiB
C

/*
* This file is part of the sigrok project.
*
* Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
* Copyright (C) 2012 Alexandru Gagniuc <mr.nuke.me@gmail.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
#include <math.h>
#include <string.h>
#include <errno.h>
#include <glib.h>
#include "libsigrok.h"
#include "libsigrok-internal.h"
#include "protocol.h"
static void handle_packet(const uint8_t *rs_packet,
struct dev_context *devc)
{
float rawval;
struct sr_datafeed_packet packet;
struct sr_datafeed_analog *analog;
/* TODO: Check malloc return value. */
analog = g_try_malloc0(sizeof(struct sr_datafeed_analog));
/* TODO: Check malloc return value. */
analog->num_samples = 1;
analog->mq = -1;
sr_rs9lcd_parse(rs_packet, &rawval, analog, NULL);
analog->data = &rawval;
if (analog->mq != -1) {
/* Got a measurement. */
sr_spew("Value: %f.", rawval);
packet.type = SR_DF_ANALOG;
packet.payload = analog;
sr_session_send(devc->cb_data, &packet);
devc->num_samples++;
}
g_free(analog);
}
static void handle_new_data(struct dev_context *devc)
{
int len;
size_t i, offset = 0;
uint8_t *rs_packet;
/* Try to get as much data as the buffer can hold. */
len = RS_DMM_BUFSIZE - devc->buflen;
len = serial_read(devc->serial, devc->buf + devc->buflen, len);
if (len < 1) {
sr_err("Serial port read error.");
return;
}
devc->buflen += len;
/* Now look for packets in that data. */
while ((devc->buflen - offset) >= RS_22_812_PACKET_SIZE) {
rs_packet = (void *)(devc->buf + offset);
if (sr_rs9lcd_packet_valid(rs_packet)) {
handle_packet(rs_packet, devc);
offset += RS_22_812_PACKET_SIZE;
} else {
offset++;
}
}
/* If we have any data left, move it to the beginning of our buffer. */
for (i = 0; i < devc->buflen - offset; i++)
devc->buf[i] = devc->buf[offset + i];
devc->buflen -= offset;
}
SR_PRIV int radioshack_dmm_receive_data(int fd, int revents, void *cb_data)
{
struct sr_dev_inst *sdi;
struct dev_context *devc;
(void)fd;
if (!(sdi = cb_data))
return TRUE;
if (!(devc = sdi->priv))
return TRUE;
if (revents == G_IO_IN) {
/* Serial data arrived. */
handle_new_data(devc);
}
if (devc->num_samples >= devc->limit_samples) {
sdi->driver->dev_acquisition_stop(sdi, cb_data);
return TRUE;
}
return TRUE;
}