+++ /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
projects / libsigrok.git / blobdiff