libsigrok/hardware/uni-t-dmm/protocol.c

285 lines
8.5 KiB
C

/*
* This file is part of the sigrok project.
*
* Copyright (C) 2012 Uwe Hermann <uwe@hermann-uwe.de>
*
* 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 2 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, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <string.h>
#include <glib.h>
#include "libsigrok.h"
#include "libsigrok-internal.h"
#include "protocol.h"
/*
* Driver for various UNI-T multimeters (and rebranded ones).
*
* Most UNI-T DMMs can be used with two (three) different PC interface cables:
* - The UT-D04 USB/HID cable, old version with Hoitek HE2325U chip.
* - The UT-D04 USB/HID cable, new version with WCH CH9325 chip.
* - The UT-D01 RS232 cable.
*
* This driver is meant to support all three cables, and various DMMs that
* can be attached to a PC via these cables. Currently only the UT-D04 cable
* (new version) is supported.
*
* The data for one DMM packet (e.g. 14 bytes if the respective DMM uses a
* Fortune Semiconductor FS9922-DMM4 chip) is spread across multiple
* 8-byte chunks.
*
* An 8-byte chunk looks like this:
* - Byte 0: 0xfz, where z is the number of actual data bytes in this chunk.
* - Bytes 1-7: z data bytes, the rest of the bytes should be ignored.
*
* Example:
* f0 00 00 00 00 00 00 00 (no data bytes)
* f2 55 77 00 00 00 00 00 (2 data bytes, 0x55 and 0x77)
* f1 d1 00 00 00 00 00 00 (1 data byte, 0xd1)
*
* Chips and serial settings used in UNI-T DMMs (and rebranded ones):
* - UNI-T UT108: ?
* - UNI-T UT109: ?
* - UNI-T UT30A: ?
* - UNI-T UT30E: ?
* - UNI-T UT60E: Fortune Semiconductor FS9721_LP3
* - UNI-T UT60G: ?
* - UNI-T UT61B: ?
* - UNI-T UT61C: ?
* - UNI-T UT61D: Fortune Semiconductor FS9922-DMM4
* - UNI-T UT61E: Cyrustek ES51922
* - UNI-T UT70B: ?
* - Voltcraft VC-820: Fortune Semiconductor FS9721_LP3
* - Voltcraft VC-840: Fortune Semiconductor FS9721_LP3
* - ...
*/
static void decode_packet(struct dev_context *devc, int dmm, const uint8_t *buf)
{
struct sr_datafeed_packet packet;
struct sr_datafeed_analog analog;
struct fs9721_info info;
float floatval;
int ret;
memset(&analog, 0, sizeof(struct sr_datafeed_analog));
/* Parse the protocol packet. */
ret = SR_ERR;
if (dmm == UNI_T_UT61D)
ret = sr_dmm_parse_fs9922(buf, &floatval, &analog);
else if (dmm == VOLTCRAFT_VC820)
ret = sr_fs9721_parse(buf, &floatval, &analog, &info);
if (ret != SR_OK) {
sr_err("Invalid DMM packet, ignoring.");
return;
}
/* Send a sample packet with one analog value. */
analog.num_samples = 1;
analog.data = &floatval;
packet.type = SR_DF_ANALOG;
packet.payload = &analog;
sr_session_send(devc->cb_data, &packet);
/* Increase sample count. */
devc->num_samples++;
}
static int hid_chip_init(struct dev_context *devc, uint16_t baudrate)
{
int ret;
uint8_t buf[5];
/* Detach kernel drivers which grabbed this device (if any). */
if (libusb_kernel_driver_active(devc->usb->devhdl, 0) == 1) {
ret = libusb_detach_kernel_driver(devc->usb->devhdl, 0);
if (ret < 0) {
sr_err("Failed to detach kernel driver: %s.",
libusb_error_name(ret));
return SR_ERR;
}
sr_dbg("Successfully detached kernel driver.");
} else {
sr_dbg("No need to detach a kernel driver.");
}
/* Claim interface 0. */
if ((ret = libusb_claim_interface(devc->usb->devhdl, 0)) < 0) {
sr_err("Failed to claim interface 0: %s.",
libusb_error_name(ret));
return SR_ERR;
}
sr_dbg("Successfully claimed interface 0.");
/* Baudrate example: 19230 baud -> HEX(19230) == 0x4b1e */
buf[0] = baudrate & 0xff; /* Baudrate, LSB */
buf[1] = (baudrate >> 8) & 0xff; /* Baudrate, MSB */
buf[2] = 0x00; /* Unknown/unused (?) */
buf[3] = 0x00; /* Unknown/unused (?) */
buf[4] = 0x03; /* Unknown, always 0x03. */
/* Send HID feature report to setup the baudrate/chip. */
sr_dbg("Sending initial HID feature report.");
sr_spew("HID init = 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x (%d baud)",
buf[0], buf[1], buf[2], buf[3], buf[4], baudrate);
ret = libusb_control_transfer(
devc->usb->devhdl, /* libusb device handle */
LIBUSB_REQUEST_TYPE_CLASS |
LIBUSB_RECIPIENT_INTERFACE |
LIBUSB_ENDPOINT_OUT,
9, /* bRequest: HID set_report */
0x300, /* wValue: HID feature, report number 0 */
0, /* wIndex: interface 0 */
(unsigned char *)&buf, /* payload buffer */
5, /* wLength: 5 bytes payload */
1000 /* timeout (ms) */);
if (ret < 0) {
sr_err("HID feature report error: %s.", libusb_error_name(ret));
return SR_ERR;
}
if (ret != 5) {
/* TODO: Handle better by also sending the remaining bytes. */
sr_err("Short packet: sent %d/5 bytes.", ret);
return SR_ERR;
}
sr_dbg("Successfully sent initial HID feature report.");
return SR_OK;
}
static void log_8byte_chunk(const uint8_t *buf)
{
sr_spew("8-byte chunk: %02x %02x %02x %02x %02x %02x %02x %02x "
"(%d data bytes)", buf[0], buf[1], buf[2], buf[3],
buf[4], buf[5], buf[6], buf[7], (buf[0] & 0x0f));
}
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]);
}
static int uni_t_dmm_receive_data(int fd, int revents, int dmm, void *cb_data)
{
struct sr_dev_inst *sdi;
struct dev_context *devc;
int i, ret, len, num_databytes_in_chunk;
uint8_t buf[CHUNK_SIZE];
uint8_t *pbuf;
static gboolean first_run = TRUE, synced_on_first_packet = FALSE;
static uint64_t data_byte_counter = 0;
(void)fd;
(void)revents;
sdi = cb_data;
devc = sdi->priv;
pbuf = devc->protocol_buf;
/* On the first run, we need to init the HID chip. */
if (first_run) {
/* TODO: The baudrate is DMM-specific (UT61D: 19230). */
if ((ret = hid_chip_init(devc, 19230)) != SR_OK) {
sr_err("HID chip init failed: %d.", ret);
return FALSE;
}
memset(pbuf, 0x00, NUM_DATA_BYTES);
first_run = FALSE;
}
memset(&buf, 0x00, CHUNK_SIZE);
/* Get data from EP2 using an interrupt transfer. */
ret = libusb_interrupt_transfer(
devc->usb->devhdl, /* libusb device handle */
LIBUSB_ENDPOINT_IN | 2, /* EP2, IN */
(unsigned char *)&buf, /* receive buffer */
CHUNK_SIZE, /* wLength */
&len, /* actually received byte count */
1000 /* timeout (ms) */);
if (ret < 0) {
sr_err("USB receive error: %s.", libusb_error_name(ret));
return FALSE;
}
if (len != CHUNK_SIZE) {
sr_err("Short packet: received %d/%d bytes.", len, CHUNK_SIZE);
/* TODO: Print the bytes? */
return FALSE;
}
log_8byte_chunk((const uint8_t *)&buf);
if (buf[0] != 0xf0) {
/* First time: Synchronize to the start of a packet. */
if (!synced_on_first_packet) {
if (dmm == UNI_T_UT61D) {
/* Valid packets start with '+' or '-'. */
if ((buf[1] != '+') && buf[1] != '-')
return TRUE;
} else if (dmm == VOLTCRAFT_VC820) {
/* Valid packets have 0x1 as high nibble. */
if (!sr_fs9721_is_packet_start(buf[1]))
return TRUE;
}
synced_on_first_packet = TRUE;
sr_spew("Successfully synchronized on first packet.");
}
num_databytes_in_chunk = buf[0] & 0x0f;
for (i = 0; i < num_databytes_in_chunk; i++)
pbuf[data_byte_counter++] = buf[1 + i];
/* TODO: Handle > 14 bytes in pbuf? Can this happen? */
if (data_byte_counter == NUM_DATA_BYTES) {
log_dmm_packet(pbuf);
data_byte_counter = 0;
if (!sr_fs9721_packet_valid(pbuf)) {
sr_err("Invalid packet.");
return TRUE;
}
decode_packet(devc, dmm, pbuf);
memset(pbuf, 0x00, NUM_DATA_BYTES);
}
}
/* Abort acquisition if we acquired enough samples. */
if (devc->limit_samples && devc->num_samples >= devc->limit_samples) {
sr_info("Requested number of samples reached.");
sdi->driver->dev_acquisition_stop(sdi, cb_data);
}
return TRUE;
}
SR_PRIV int uni_t_ut61d_receive_data(int fd, int revents, void *cb_data)
{
return uni_t_dmm_receive_data(fd, revents, UNI_T_UT61D, cb_data);
}
SR_PRIV int voltcraft_vc820_receive_data(int fd, int revents, void *cb_data)
{
return uni_t_dmm_receive_data(fd, revents, VOLTCRAFT_VC820, cb_data);
}