libsigrok_hw_brymen_dmm_la_SOURCES = \
api.c \
+ parser.c \
protocol.c \
protocol.h
*/
#include <glib.h>
+#include <errno.h>
+#include <string.h>
+#include <fcntl.h>
#include "libsigrok.h"
#include "libsigrok-internal.h"
#include "protocol.h"
+static const int hwopts[] = {
+ SR_CONF_CONN,
+ SR_CONF_SERIALCOMM,
+ 0,
+};
+
+static const int hwcaps[] = {
+ SR_CONF_MULTIMETER,
+ SR_CONF_LIMIT_SAMPLES,
+ SR_CONF_CONTINUOUS,
+ SR_CONF_LIMIT_MSEC,
+ 0,
+};
+
SR_PRIV struct sr_dev_driver brymen_dmm_driver_info;
static struct sr_dev_driver *di = &brymen_dmm_driver_info;
+static int hw_init(struct sr_context *sr_ctx)
+{
+ struct drv_context *drvc;
+
+ if (!(drvc = g_try_malloc0(sizeof(struct drv_context)))) {
+ sr_err("Driver context malloc failed.");
+ return SR_ERR_MALLOC;
+ }
+
+ drvc->sr_ctx = sr_ctx;
+ di->priv = drvc;
+
+ return SR_OK;
+}
+
+static void free_instance(void *inst)
+{
+ struct sr_dev_inst *sdi;
+ struct dev_context *devc;
+ if (!(sdi = inst))
+ return;
+ if (!(devc = sdi->priv))
+ return;
+ sr_serial_dev_inst_free(devc->serial);
+ sr_dev_inst_free(sdi);
+}
+
/* Properly close and free all devices. */
static int clear_instances(void)
{
- struct sr_dev_inst *sdi;
struct drv_context *drvc;
- struct dev_context *devc;
- GSList *l;
if (!(drvc = di->priv))
return SR_OK;
- for (l = drvc->instances; l; l = l->next) {
- if (!(sdi = l->data))
- continue;
- if (!(devc = sdi->priv))
- continue;
-
- /* TODO */
-
- sr_dev_inst_free(sdi);
- }
-
- g_slist_free(drvc->instances);
+ g_slist_free_full(drvc->instances, free_instance);
drvc->instances = NULL;
return SR_OK;
}
-static int hw_init(void)
+static GSList *brymen_scan(const char *conn, const char *serialcomm)
{
+ struct sr_dev_inst *sdi;
+ struct dev_context *devc;
struct drv_context *drvc;
+ struct sr_probe *probe;
+ struct sr_serial_dev_inst *serial;
+ GSList *devices;
+ int ret;
- if (!(drvc = g_try_malloc0(sizeof(struct drv_context)))) {
- sr_err("Driver context malloc failed.");
- return SR_ERR_MALLOC;
+ if (!(serial = sr_serial_dev_inst_new(conn, serialcomm)))
+ return NULL;
+
+ if (serial_open(serial, SERIAL_RDWR|SERIAL_NONBLOCK) != SR_OK)
+ return NULL;
+
+ sr_info("Probing port %s.", conn);
+
+ devices = NULL;
+
+ /* Request reading */
+ if (brymen_packet_request(serial) == -1) {
+ sr_err("Unable to send command. code: %d.", errno);
+ goto scan_cleanup;
}
- /* TODO */
+ uint8_t buf[128];
+ size_t len = 128;
- di->priv = drvc;
+ ret = brymen_stream_detect(serial, buf, &len, brymen_packet_length,
+ brymen_packet_is_valid, 1000, 9600);
+ if (ret != SR_OK)
+ goto scan_cleanup;
- return SR_OK;
+ sr_info("Found device on port %s.", conn);
+
+ if (!(sdi = sr_dev_inst_new(0, SR_ST_INACTIVE, "Brymen", "BM85x", "")))
+ goto scan_cleanup;
+
+ if (!(devc = g_try_malloc0(sizeof(struct dev_context)))) {
+ sr_err("Device context malloc failed.");
+ goto scan_cleanup;
+ }
+
+ devc->serial = serial;
+ drvc = di->priv;
+ sdi->priv = devc;
+ sdi->driver = di;
+
+ if (!(probe = sr_probe_new(0, SR_PROBE_ANALOG, TRUE, "P1")))
+ goto scan_cleanup;
+
+ sdi->probes = g_slist_append(sdi->probes, probe);
+ drvc->instances = g_slist_append(drvc->instances, sdi);
+ devices = g_slist_append(devices, sdi);
+
+
+scan_cleanup:
+ serial_close(serial);
+
+ return devices;
}
static GSList *hw_scan(GSList *options)
{
struct drv_context *drvc;
- GSList *devices;
+ struct sr_config *src;
+ GSList *devices, *l;
+ const char *conn, *serialcomm;
(void)options;
drvc = di->priv;
drvc->instances = NULL;
- /* TODO */
+ conn = serialcomm = NULL;
+ for (l = options; l; l = l->next) {
+ src = l->data;
+ switch (src->key) {
+ case SR_CONF_CONN:
+ conn = src->value;
+ break;
+ case SR_CONF_SERIALCOMM:
+ serialcomm = src->value;
+ break;
+ }
+ }
+ if (!conn) {
+ return NULL;
+ }
+
+ if (serialcomm) {
+ /* Use the provided comm specs. */
+ devices = brymen_scan(conn, serialcomm);
+ } else {
+ /* But 9600 8N1 should work all of the time */
+ devices = brymen_scan(conn, "9600/8n1/dtr=1/rts=1");
+ }
return devices;
}
static int hw_dev_open(struct sr_dev_inst *sdi)
{
- /* TODO */
+ struct dev_context *devc;
+
+ if (!(devc = sdi->priv)) {
+ sr_err("sdi->priv was NULL.");
+ return SR_ERR_BUG;
+ }
+
+ if (serial_open(devc->serial, SERIAL_RDWR | SERIAL_NONBLOCK) != SR_OK)
+ return SR_ERR;
+
+ sdi->status = SR_ST_ACTIVE;
return SR_OK;
}
static int hw_dev_close(struct sr_dev_inst *sdi)
{
- /* TODO */
+ struct dev_context *devc;
+
+ if (!(devc = sdi->priv)) {
+ sr_err("sdi->priv was NULL.");
+ return SR_ERR_BUG;
+ }
+
+ if (devc->serial && devc->serial->fd != -1) {
+ serial_close(devc->serial);
+ sdi->status = SR_ST_INACTIVE;
+ }
return SR_OK;
}
{
clear_instances();
- /* TODO */
-
return SR_OK;
}
-static int hw_info_get(int info_id, const void **data,
+static int config_list(int key, const void **data,
const struct sr_dev_inst *sdi)
{
- switch (info_id) {
- /* TODO */
+ (void)sdi;
+
+ switch (key) {
+ case SR_CONF_SCAN_OPTIONS:
+ *data = hwopts;
+ break;
+ case SR_CONF_DEVICE_OPTIONS:
+ *data = hwcaps;
+ break;
default:
- sr_err("Unknown info_id: %d.", info_id);
+ sr_err("Unknown config key: %d.", key);
return SR_ERR_ARG;
}
return SR_OK;
}
-static int hw_dev_config_set(const struct sr_dev_inst *sdi, int hwcap,
- const void *value)
+static int hw_dev_config_set(int id, const void *value,
+ const struct sr_dev_inst *sdi)
{
+ struct dev_context *devc;
int ret;
if (sdi->status != SR_ST_ACTIVE) {
return SR_ERR;
}
+ if (!(devc = sdi->priv)) {
+ sr_err("sdi->priv was NULL.");
+ return SR_ERR_BUG;
+ }
+
ret = SR_OK;
- switch (hwcap) {
- /* TODO */
+ switch (id) {
+ case SR_CONF_LIMIT_SAMPLES:
+ devc->limit_samples = *(const uint64_t*)value;
+ break;
+ case SR_CONF_LIMIT_MSEC:
+ devc->limit_msec = *(const uint64_t*)value;
+ break;
default:
- sr_err("Unknown hardware capability: %d.", hwcap);
+ sr_err("Unknown hardware capability: %d.", id);
ret = SR_ERR_ARG;
}
static int hw_dev_acquisition_start(const struct sr_dev_inst *sdi,
void *cb_data)
{
- /* TODO */
+ struct sr_datafeed_packet packet;
+ struct sr_datafeed_header header;
+ struct dev_context *devc;
+
+ if (!(devc = sdi->priv)) {
+ sr_err("sdi->priv was NULL.");
+ return SR_ERR_BUG;
+ }
+
+ sr_dbg("Starting acquisition.");
+
+ devc->cb_data = cb_data;
+
+ /*
+ * Reset the number of samples to take. If we've already collected our
+ * quota, but we start a new session, and don't reset this, we'll just
+ * quit without acquiring any new samples.
+ */
+ devc->num_samples = 0;
+ devc->starttime = g_get_monotonic_time();
+
+ /* Send header packet to the session bus. */
+ sr_dbg("Sending SR_DF_HEADER.");
+ packet.type = SR_DF_HEADER;
+ packet.payload = &header;
+ header.feed_version = 1;
+ gettimeofday(&header.starttime, NULL);
+ sr_session_send(devc->cb_data, &packet);
+
+ /* Poll every 50ms, or whenever some data comes in. */
+ sr_source_add(devc->serial->fd, G_IO_IN, 50,
+ brymen_dmm_receive_data, (void *)sdi);
return SR_OK;
}
-static int hw_dev_acquisition_stop(const struct sr_dev_inst *sdi,
- void *cb_data)
+static int hw_dev_acquisition_stop(struct sr_dev_inst *sdi, void *cb_data)
{
- (void)cb_data;
+ struct sr_datafeed_packet packet;
+ struct dev_context *devc;
if (sdi->status != SR_ST_ACTIVE) {
sr_err("Device inactive, can't stop acquisition.");
return SR_ERR;
}
- /* TODO */
+ if (!(devc = sdi->priv)) {
+ sr_err("sdi->priv was NULL.");
+ return SR_ERR_BUG;
+ }
+
+ sr_dbg("Stopping acquisition.");
+
+ sr_source_remove(devc->serial->fd);
+ hw_dev_close((struct sr_dev_inst *)sdi);
+
+ /* Send end packet to the session bus. */
+ sr_dbg("Sending SR_DF_END.");
+ packet.type = SR_DF_END;
+ sr_session_send(cb_data, &packet);
return SR_OK;
}
SR_PRIV struct sr_dev_driver brymen_dmm_driver_info = {
.name = "brymen-dmm",
- .longname = "brymen-dmm",
+ .longname = "Brymen BM850 series",
.api_version = 1,
.init = hw_init,
.cleanup = hw_cleanup,
.dev_clear = clear_instances,
.dev_open = hw_dev_open,
.dev_close = hw_dev_close,
- .info_get = hw_info_get,
- .dev_config_set = hw_dev_config_set,
+ .config_list = config_list,
+ .config_set = hw_dev_config_set,
.dev_acquisition_start = hw_dev_acquisition_start,
.dev_acquisition_stop = hw_dev_acquisition_stop,
.priv = NULL,
--- /dev/null
+/*
+ * This file is part of the sigrok project.
+ *
+ * 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 "protocol.h"
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+
+/*
+ * Flags passed from the DMM.
+ */
+struct brymen_flags {
+ gboolean low_batt;
+ gboolean decibel, duty_cycle, hertz, amp, beep, ohm, fahrenheit;
+ gboolean celsius, capacitance, diode, volt, dc, ac;
+};
+
+struct bm850_command {
+ uint8_t dle;
+ uint8_t stx;
+ uint8_t cmd;
+ uint8_t arg[2];
+ uint8_t checksum;
+ uint8_t dle2;
+ uint8_t etx;
+};
+
+struct brymen_header {
+ uint8_t dle;
+ uint8_t stx;
+ uint8_t cmd;
+ uint8_t len;
+};
+
+struct brymen_tail {
+ uint8_t checksum;
+ uint8_t dle;
+ uint8_t etx;
+};
+
+/*
+ * We only have one command because we only support the BM-857. However, the
+ * driver is easily extensible to support more models, as the protocols are very
+ * similar.
+ */
+enum {
+ BM_CMD_REQUEST_READING = 0x00,
+};
+
+
+static int bm_send_command(uint8_t command, uint8_t arg1, uint8_t arg2,
+ struct sr_serial_dev_inst *serial)
+{
+ struct bm850_command cmdout = {
+ .dle = 0x10, .stx = 0x02,
+ .cmd = command,
+ .arg = {arg1, arg2},
+ .checksum = arg1^arg2, .dle2 = 0x10, .etx = 0x03};
+ int written;
+
+ /* TODO: How do we compute the checksum? Hardware seems to ignore it */
+
+ /* Request reading */
+ written = serial_write(serial, &cmdout, sizeof(cmdout));
+ if(written != sizeof(cmdout))
+ return SR_ERR;
+
+ return SR_OK;
+}
+
+SR_PRIV int brymen_packet_request(struct sr_serial_dev_inst *serial)
+{
+ return bm_send_command(BM_CMD_REQUEST_READING, 0, 0, serial);
+}
+
+SR_PRIV int brymen_packet_length(const uint8_t *buf, int *len)
+{
+ struct brymen_header *hdr;
+ const int brymen_max_packet_len = 22;
+ int packet_len;
+ const size_t buflen = *len;
+
+ hdr = (void*)buf;
+
+ /* Did we receive a complete header yet? */
+ if (buflen < sizeof(*hdr) )
+ return PACKET_NEED_MORE_DATA;
+
+ if (hdr->dle != 0x10 || hdr->stx != 0x02)
+ return PACKET_INVALID_HEADER;
+
+ /* Our packet includes the header, the payload, and the tail */
+ packet_len = sizeof(*hdr) + hdr->len + sizeof(struct brymen_tail);
+
+ /* In case we pick up an invalid header, limit our search */
+ if (packet_len > brymen_max_packet_len) {
+ sr_spew("Header specifies an invalid payload length: %i.",
+ hdr->len);
+ return PACKET_INVALID_HEADER;
+ }
+
+ *len = packet_len;
+ sr_spew("Expecting a %d-byte packet.", *len);
+ return PACKET_HEADER_OK;
+}
+
+SR_PRIV gboolean brymen_packet_is_valid(const uint8_t *buf)
+{
+ struct brymen_header *hdr;
+ struct brymen_tail *tail;
+ int i;
+ uint8_t chksum = 0;
+ const uint8_t *payload = buf + sizeof(struct brymen_header);
+
+ hdr = (void*)buf;
+ tail = (void*)(payload + hdr->len);
+
+ for (i = 0; i< hdr->len; i++)
+ chksum ^= payload[i];
+
+ if (tail->checksum != chksum) {
+ sr_dbg("Packet has invalid checksum 0x%.2x. Expected 0x%.2x",
+ chksum, tail->checksum);
+ return FALSE;
+ }
+
+ return TRUE;
+}
+
+static int parse_value(const char *strbuf, const int len, float *floatval)
+{
+ int s, d;
+ char str[32];
+
+ if (strstr(strbuf, "OL")) {
+ sr_dbg("Overlimit.");
+ *floatval = INFINITY;
+ return SR_OK;
+ }
+
+ memset(str, 0, sizeof(str));
+ /* Spaces may interfere with strtod parsing the exponent. Strip them */
+ for (s = 0, d = 0; s < len; s++)
+ if (strbuf[s] != ' ')
+ str[d++] = strbuf[s];
+ /* YES, it's that simple !*/
+ *floatval = strtod(str, NULL);
+
+ return SR_OK;
+}
+static void parse_flags(const uint8_t *buf, struct brymen_flags *info)
+{
+ const uint8_t * bfunc = buf + sizeof(struct brymen_header);
+
+ info->low_batt = (bfunc[3] & (1 << 7)) != 0;
+
+ info->decibel = (bfunc[1] & (1 << 5)) != 0;
+ info->duty_cycle = (bfunc[1] & (1 << 3)) != 0;
+ info->hertz = (bfunc[1] & (1 << 2)) != 0;
+ info->amp = (bfunc[1] & (1 << 1)) != 0;
+ info->beep = (bfunc[1] & (1 << 0)) != 0;
+
+ info->ohm = (bfunc[0] & (1 << 7)) != 0;
+ info->fahrenheit = (bfunc[0] & (1 << 6)) != 0;
+ info->celsius = (bfunc[0] & (1 << 5)) != 0;
+ info->diode = (bfunc[0] & (1 << 4)) != 0;
+ info->capacitance = (bfunc[0] & (1 << 3)) != 0;
+ info->volt = (bfunc[0] & (1 << 2)) != 0;
+ info->dc = (bfunc[0] & (1 << 1)) != 0;
+ info->ac = (bfunc[0] & (1 << 0)) != 0;
+}
+
+SR_PRIV int sr_brymen_parse(const uint8_t *buf, float *floatval,
+ struct sr_datafeed_analog *analog, void *info)
+{
+ struct brymen_flags flags;
+ struct brymen_header *hdr = (void*) buf;
+ const uint8_t *bfunc = buf + sizeof(struct brymen_header);
+ int asciilen;
+
+ (void)info;
+ analog->mqflags = 0;
+
+ /* Give some debug info about the package */
+ asciilen = hdr->len - 4;
+ sr_dbg("DMM flags: %.2x %.2x %.2x %.2x",
+ bfunc[3], bfunc[2], bfunc[1], bfunc[0]);
+ /* Value is an ASCII string */
+ sr_dbg("DMM packet: \"%.*s\"", asciilen, bfunc + 4);
+
+ parse_flags(buf, &flags);
+ parse_value((const char*)(bfunc + 4), asciilen, floatval);
+
+ if (flags.volt) {
+ analog->mq = SR_MQ_VOLTAGE;
+ analog->unit = SR_UNIT_VOLT;
+ }
+ if (flags.amp) {
+ analog->mq = SR_MQ_CURRENT;
+ analog->unit = SR_UNIT_AMPERE;
+ }
+ if (flags.ohm) {
+ if (flags.beep)
+ analog->mq = SR_MQ_CONTINUITY;
+ else
+ analog->mq = SR_MQ_RESISTANCE;
+ analog->unit = SR_UNIT_OHM;
+ }
+ if (flags.hertz) {
+ analog->mq = SR_MQ_FREQUENCY;
+ analog->unit = SR_UNIT_HERTZ;
+ }
+ if (flags.duty_cycle) {
+ analog->mq = SR_MQ_DUTY_CYCLE;
+ analog->unit = SR_UNIT_PERCENTAGE;
+ }
+ if (flags.capacitance) {
+ analog->mq = SR_MQ_CAPACITANCE;
+ analog->unit = SR_UNIT_FARAD;
+ }
+ if (flags.fahrenheit) {
+ analog->mq = SR_MQ_TEMPERATURE;
+ analog->unit = SR_UNIT_FAHRENHEIT;
+ }
+ if (flags.celsius) {
+ analog->mq = SR_MQ_TEMPERATURE;
+ analog->unit = SR_UNIT_CELSIUS;
+ }
+ if (flags.capacitance) {
+ analog->mq = SR_MQ_CAPACITANCE;
+ analog->unit = SR_UNIT_FARAD;
+ }
+ /*
+ * The high-end brymen models have a configurable reference impedance.
+ * When the reference impedance is changed, the DMM sends one packet
+ * with the value of the new reference impedance. Both decibel and ohm
+ * flags are set in this case, so we must be careful to correctly
+ * identify the value as ohm, not dBmW
+ */
+ if (flags.decibel && !flags.ohm) {
+ analog->mq = SR_MQ_POWER;
+ analog->unit = SR_UNIT_DECIBEL_MW;
+ /*
+ * For some reason, dBm measurements are sent by the multimeter
+ * with a value three orders of magnitude smaller than the
+ * displayed value.
+ * */
+ *floatval *= 1000;
+ }
+
+ if (flags.diode)
+ analog->mqflags |= SR_MQFLAG_DIODE;
+ /* We can have both AC+DC in a single measurement */
+ if (flags.ac)
+ analog->mqflags |= SR_MQFLAG_AC;
+ if (flags.dc)
+ analog->mqflags |= SR_MQFLAG_DC;
+
+ if (flags.low_batt)
+ sr_info("Low battery!");
+
+ return SR_OK;
+}
\ No newline at end of file
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
-#include <stdlib.h>
-#include <glib.h>
#include "libsigrok.h"
#include "libsigrok-internal.h"
#include "protocol.h"
+#include <string.h>
+
+/* --- parser.c --- */
+SR_PRIV int sr_brymen_parse(const uint8_t *buf, float *floatval,
+ struct sr_datafeed_analog *analog, void *info);
+
+
+static void handle_packet(const uint8_t *buf, struct sr_dev_inst *sdi)
+{
+ float floatval;
+ struct dev_context *devc;
+ struct sr_datafeed_packet packet;
+ struct sr_datafeed_analog analog;
+
+ devc = sdi->priv;
+
+ analog.num_samples = 1;
+ analog.mq = -1;
+
+ sr_brymen_parse(buf, &floatval, &analog, NULL);
+ analog.data = &floatval;
+
+ analog.probes = sdi->probes;
+
+ if (analog.mq != -1) {
+ /* Got a measurement. */
+ packet.type = SR_DF_ANALOG;
+ packet.payload = &analog;
+ sr_session_send(devc->cb_data, &packet);
+ devc->num_samples++;
+ }
+}
+
+static void handle_new_data(struct sr_dev_inst *sdi)
+{
+ struct dev_context *devc;
+ int len, status, offset = 0;
+
+ devc = sdi->priv;
+
+ /* Try to get as much data as the buffer can hold. */
+ len = DMM_BUFSIZE - devc->buflen;
+ len = serial_read(devc->serial, devc->buf + devc->buflen, len);
+ if (len < 1) {
+ sr_err("Serial port read error: %d.", len);
+ return;
+ }
+ devc->buflen += len;
+ status = PACKET_INVALID_HEADER;
+
+ /* Now look for packets in that data. */
+ while (status != PACKET_NEED_MORE_DATA) {
+ /* We don't have a header, look for one */
+ if (devc->next_packet_len == 0) {
+ len = devc->buflen - offset;
+ status = brymen_packet_length(devc->buf + offset, &len);
+ if (status == PACKET_HEADER_OK) {
+ /* We know how large the packet will be */
+ devc->next_packet_len = len;
+ } else if (status == PACKET_NEED_MORE_DATA) {
+ /* We did not yet receive the complete header */
+ devc->next_packet_len = 0;
+ break;
+ } else {
+ /* Invalid header. Move on */
+ devc->next_packet_len = 0;
+ offset++;
+ continue;
+ }
+ }
+
+ /* We know how the packet size, but did we receive all of it? */
+ if (devc->buflen - offset < devc->next_packet_len)
+ break;
+
+ /* We should have a full packet here, so we can check it */
+ if (brymen_packet_is_valid(devc->buf + offset)) {
+ handle_packet(devc->buf + offset, sdi);
+ offset += devc->next_packet_len;
+ } else {
+ offset++;
+ }
+ /* We are done with this packet. Look for a new one. */
+ devc->next_packet_len = 0;
+ }
+
+ /* If we have any data left, move it to the beginning of our buffer. */
+ memmove(devc->buf, devc->buf + offset, devc->buflen - offset);
+ devc->buflen -= offset;
+}
+
SR_PRIV int brymen_dmm_receive_data(int fd, int revents, void *cb_data)
{
- const struct sr_dev_inst *sdi;
+ struct sr_dev_inst *sdi;
struct dev_context *devc;
+ int ret;
+ int64_t time;
+
+ (void)fd;
if (!(sdi = cb_data))
return TRUE;
return TRUE;
if (revents == G_IO_IN) {
- /* TODO */
+ /* Serial data arrived. */
+ handle_new_data(sdi);
+ } else {
+ /* Timeout, send another packet request. */
+ ret = brymen_packet_request(devc->serial);
+ if (ret < 0) {
+ sr_err("Failed to request packet: %d.", ret);
+ return FALSE;
+ }
+ }
+
+ if (devc->limit_samples && devc->num_samples >= devc->limit_samples) {
+ sr_info("Requested number of samples reached, stopping.");
+ sdi->driver->dev_acquisition_stop(sdi, cb_data);
+ return TRUE;
+ }
+
+ if (devc->limit_msec) {
+ time = (g_get_monotonic_time() - devc->starttime) / 1000;
+ if (time > (int64_t)devc->limit_msec) {
+ sr_info("Requested time limit reached, stopping.");
+ sdi->driver->dev_acquisition_stop(sdi, cb_data);
+ return TRUE;
+ }
}
return TRUE;
}
+
+/**
+ * Try to find a valid packet in a serial data stream.
+ *
+ * @param serial Previously initialized serial port structure.
+ * @param buf Buffer containing the bytes to write.
+ * @param buflen Size of the buffer.
+ * @param packet_size Callback that assesses the size of the incoming 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.
+ *
+ * @return SR_OK if a valid packet is found within the given timeout,
+ * SR_ERR upon failure.
+ */
+SR_PRIV int brymen_stream_detect(struct sr_serial_dev_inst *serial,
+ uint8_t *buf, size_t *buflen,
+ packet_length_t get_packet_size,
+ packet_valid_t is_valid,
+ uint64_t timeout_ms, int baudrate)
+{
+ int64_t start, time, byte_delay_us;
+ size_t ibuf, i, maxlen;
+ int status, len, packet_len, stream_len;
+
+ maxlen = *buflen;
+
+ sr_dbg("Detecting packets on FD %d (timeout = %" PRIu64
+ "ms, baudrate = %d).", serial->fd, timeout_ms, baudrate);
+
+ /* Assume 8n1 transmission. That is 10 bits for every byte. */
+ byte_delay_us = 10 * (1000000 / baudrate);
+ start = g_get_monotonic_time();
+
+ packet_len = i = ibuf = len = 0;
+ while (ibuf < maxlen) {
+ len = serial_read(serial, &buf[ibuf], maxlen - ibuf);
+ if (len > 0) {
+ ibuf += len;
+ sr_spew("Read %d bytes", len);
+ }
+
+ time = g_get_monotonic_time() - start;
+ time /= 1000;
+
+ stream_len = ibuf - i;
+ if (stream_len > 0 && packet_len == 0) {
+ /* How large of a packet are we expecting? */
+ packet_len = stream_len;
+ status = get_packet_size(&buf[i], &packet_len);
+ switch(status) {
+ case PACKET_HEADER_OK:
+ /* We know how much data we need to wait for */
+ break;
+ case PACKET_NEED_MORE_DATA:
+ /* We did not receive the full header */
+ packet_len = 0;
+ break;
+ case PACKET_INVALID_HEADER:
+ default:
+ /*
+ * We had enough data, but here was an error in
+ * parsing the header. Restart parsing from the
+ * next byte
+ */
+ packet_len = 0;
+ i++;
+ break;
+ }
+ }
+
+ if ( (stream_len >= packet_len) && (packet_len != 0) ) {
+ /* We have at least a packet's worth of data. */
+ if (is_valid(&buf[i])) {
+ sr_spew("Found valid %d-byte packet after "
+ "%" PRIu64 "ms.", packet_len, time);
+ *buflen = ibuf;
+ return SR_OK;
+ } else {
+ sr_spew("Got %d bytes, but not a valid "
+ "packet.", packet_len);
+
+ }
+ /* Not a valid packet. Continue searching. */
+ i++;
+ packet_len = 0;
+ }
+ if (time >= (int64_t)timeout_ms) {
+ /* Timeout */
+ sr_dbg("Detection timed out after %dms.", time);
+ break;
+ }
+ g_usleep(byte_delay_us);
+ }
+
+ *buflen = ibuf;
+ sr_err("Didn't find a valid packet (read %d bytes).", ibuf);
+
+ return SR_ERR;
+}
#define sr_warn(s, args...) sr_warn(DRIVER_LOG_DOMAIN s, ## args)
#define sr_err(s, args...) sr_err(DRIVER_LOG_DOMAIN s, ## args)
+
+#define DMM_BUFSIZE 256
+
+enum packet_len_status {
+ PACKET_HEADER_OK,
+ PACKET_NEED_MORE_DATA,
+ PACKET_INVALID_HEADER,
+};
+
/** Private, per-device-instance driver context. */
struct dev_context {
/** The current sampling limit (in number of samples). */
/** The current number of already received samples. */
uint64_t num_samples;
+
+ /** Start time of acquisition session */
+ int64_t starttime;
+
+ struct sr_serial_dev_inst *serial;
+
+ uint8_t buf[DMM_BUFSIZE];
+ int bufoffset;
+ int buflen;
+ int next_packet_len;
};
+/**
+ * Callback that assesses the size and status of the incoming packet
+ *
+ * @return PACKET_HEADER_OK - This is a proper packet header.
+ * PACKET_NEED_MORE_DATA The buffer does not contain the entire header
+ * PACKET_INVALID_HEADER Not a valid start of packet.
+ */
+typedef int (*packet_length_t)(const uint8_t *buf, int *len);
+
SR_PRIV int brymen_dmm_receive_data(int fd, int revents, void *cb_data);
+SR_PRIV int brymen_packet_request(struct sr_serial_dev_inst *serial);
+
+SR_PRIV int brymen_packet_length(const uint8_t *buf, int *len);
+SR_PRIV gboolean brymen_packet_is_valid(const uint8_t *buf);
+SR_PRIV int brymen_stream_detect(struct sr_serial_dev_inst *serial,
+ uint8_t *buf, size_t *buflen,
+ packet_length_t get_packet_size,
+ packet_valid_t is_valid,
+ uint64_t timeout_ms, int baudrate);
#endif