src/hardware/colead-slm/protocol.c

   1 /*
   2  * This file is part of the libsigrok project.
   3  *
   4  * Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
   5  *
   6  * This program is free software: you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation, either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <config.h>
  21 #include <stdlib.h>
  22 #include <glib.h>
  23 #include <string.h>
  24 #include <libsigrok/libsigrok.h>
  25 #include "libsigrok-internal.h"
  26 #include "protocol.h"
  27
  28 static void process_packet(const struct sr_dev_inst *sdi)
  29 {
  30         struct dev_context *devc;
  31         struct sr_datafeed_packet packet;
  32         struct sr_datafeed_analog analog;
  33         struct sr_analog_encoding encoding;
  34         struct sr_analog_meaning meaning;
  35         struct sr_analog_spec spec;
  36         GString *dbg;
  37         float fvalue;
  38         int checksum, mode, i;
  39
  40         devc = sdi->priv;
  41         if (sr_log_loglevel_get() >= SR_LOG_SPEW) {
  42                 dbg = g_string_sized_new(128);
  43                 g_string_printf(dbg, "received packet:");
  44                 for (i = 0; i < 10; i++)
  45                         g_string_append_printf(dbg, " %.2x", (devc->buf)[i]);
  46                 sr_spew("%s", dbg->str);
  47                 g_string_free(dbg, TRUE);
  48         }
  49
  50         if (devc->buf[0] != 0x08 || devc->buf[1] != 0x04) {
  51                 sr_dbg("invalid packet header.");
  52                 return;
  53         }
  54
  55         if (devc->buf[8] != 0x01) {
  56                 sr_dbg("invalid measurement.");
  57                 return;
  58         }
  59
  60         checksum = 0;
  61         for (i = 0; i < 9; i++)
  62                 checksum += devc->buf[i];
  63         if ((checksum & 0xff) != devc->buf[9]) {
  64                 sr_dbg("invalid packet checksum.");
  65                 return;
  66         }
  67
  68         fvalue = 0.0;
  69         for (i = 3; i < 8; i++) {
  70                 if (devc->buf[i] > 0x09)
  71                         continue;
  72                 fvalue *= 10;
  73                 fvalue += devc->buf[i];
  74         }
  75         fvalue /= 10;
  76
  77         sr_analog_init(&analog, &encoding, &meaning, &spec, 1);
  78         analog.meaning->mq = SR_MQ_SOUND_PRESSURE_LEVEL;
  79         analog.meaning->unit = SR_UNIT_DECIBEL_SPL;
  80         analog.meaning->channels = sdi->channels;
  81         analog.num_samples = 1;
  82         analog.data = &fvalue;
  83
  84         /* High nibble should only have 0x01 or 0x02. */
  85         mode = (devc->buf[2] >> 4) & 0x0f;
  86         if (mode == 0x02)
  87                 analog.meaning->mqflags |= SR_MQFLAG_HOLD;
  88         else if (mode != 0x01) {
  89                 sr_dbg("unknown measurement mode 0x%.2x", mode);
  90                 return;
  91         }
  92
  93         /* Low nibble has 14 combinations of direct/long-term average,
  94          * time scale of that average, frequency weighting, and time
  95          * weighting. */
  96         mode = devc->buf[2] & 0x0f;
  97         switch (mode) {
  98         case 0x0:
  99                 analog.meaning->mqflags |= SR_MQFLAG_SPL_FREQ_WEIGHT_A \
 100                                 | SR_MQFLAG_SPL_TIME_WEIGHT_F;
 101                 break;
 102         case 0x1:
 103                 analog.meaning->mqflags |= SR_MQFLAG_SPL_FREQ_WEIGHT_A \
 104                                 | SR_MQFLAG_SPL_TIME_WEIGHT_S;
 105                 break;
 106         case 0x2:
 107                 analog.meaning->mqflags |= SR_MQFLAG_SPL_FREQ_WEIGHT_C \
 108                                 | SR_MQFLAG_SPL_TIME_WEIGHT_F;
 109                 break;
 110         case 0x3:
 111                 analog.meaning->mqflags |= SR_MQFLAG_SPL_FREQ_WEIGHT_C \
 112                                 | SR_MQFLAG_SPL_TIME_WEIGHT_S;
 113                 break;
 114         case 0x4:
 115                 analog.meaning->mqflags |= SR_MQFLAG_SPL_FREQ_WEIGHT_FLAT \
 116                                 | SR_MQFLAG_SPL_TIME_WEIGHT_F;
 117                 break;
 118         case 0x5:
 119                 analog.meaning->mqflags |= SR_MQFLAG_SPL_FREQ_WEIGHT_FLAT \
 120                                 | SR_MQFLAG_SPL_TIME_WEIGHT_S;
 121                 break;
 122         case 0x6:
 123                 analog.meaning->mqflags |= SR_MQFLAG_SPL_PCT_OVER_ALARM \
 124                                 | SR_MQFLAG_SPL_FREQ_WEIGHT_A \
 125                                 | SR_MQFLAG_SPL_TIME_WEIGHT_F;
 126                 break;
 127         case 0x7:
 128                 analog.meaning->mqflags |= SR_MQFLAG_SPL_PCT_OVER_ALARM \
 129                                 | SR_MQFLAG_SPL_FREQ_WEIGHT_A \
 130                                 | SR_MQFLAG_SPL_TIME_WEIGHT_S;
 131                 break;
 132         case 0x8:
 133                 /* 10-second mean, but we don't have MQ flags to express it. */
 134                 analog.meaning->mqflags |= SR_MQFLAG_SPL_LAT \
 135                                 | SR_MQFLAG_SPL_FREQ_WEIGHT_A \
 136                                 | SR_MQFLAG_SPL_TIME_WEIGHT_F;
 137                 break;
 138         case 0x9:
 139                 /* Mean over a time period between 11 seconds and 24 hours.
 140                  * Which is so silly that there's no point in expressing
 141                  * either this or the previous case. */
 142                 analog.meaning->mqflags |= SR_MQFLAG_SPL_LAT \
 143                                 | SR_MQFLAG_SPL_FREQ_WEIGHT_A \
 144                                 | SR_MQFLAG_SPL_TIME_WEIGHT_F;
 145                 break;
 146         case 0xa:
 147                 /* 10-second mean. */
 148                 analog.meaning->mqflags |= SR_MQFLAG_SPL_LAT \
 149                                 | SR_MQFLAG_SPL_FREQ_WEIGHT_A \
 150                                 | SR_MQFLAG_SPL_TIME_WEIGHT_S;
 151                 break;
 152         case 0xb:
 153                 /* Mean over a time period between 11 seconds and 24 hours. */
 154                 analog.meaning->mqflags |= SR_MQFLAG_SPL_LAT \
 155                                 | SR_MQFLAG_SPL_FREQ_WEIGHT_A \
 156                                 | SR_MQFLAG_SPL_TIME_WEIGHT_S;
 157                 break;
 158         case 0xc:
 159                 /* Internal calibration on 1kHz sine at 94dB, not useful
 160                  * to anything but the device. */
 161                 analog.meaning->mqflags |= SR_MQFLAG_SPL_FREQ_WEIGHT_FLAT;
 162                 break;
 163         case 0xd:
 164                 /* Internal calibration on 1kHz sine at 94dB, not useful
 165                  * to anything but the device. */
 166                 analog.meaning->mqflags |= SR_MQFLAG_SPL_FREQ_WEIGHT_FLAT;
 167                 break;
 168         default:
 169                 sr_dbg("unknown configuration 0x%.2x", mode);
 170                 return;
 171         }
 172
 173         packet.type = SR_DF_ANALOG;
 174         packet.payload = &analog;
 175         sr_session_send(sdi, &packet);
 176
 177         sr_sw_limits_update_samples_read(&devc->limits, 1);
 178
 179         if (sr_sw_limits_check(&devc->limits))
 180                 sdi->driver->dev_acquisition_stop((struct sr_dev_inst *)sdi);
 181 }
 182
 183 SR_PRIV int colead_slm_receive_data(int fd, int revents, void *cb_data)
 184 {
 185         const struct sr_dev_inst *sdi;
 186         struct dev_context *devc;
 187         struct sr_serial_dev_inst *serial;
 188         int delay_ms, len;
 189         char buf[128];
 190
 191         (void)fd;
 192
 193         if (!(sdi = cb_data))
 194                 return TRUE;
 195
 196         if (!(devc = sdi->priv))
 197                 return TRUE;
 198
 199         if (revents != G_IO_IN)
 200                 /* Timeout event. */
 201                 return TRUE;
 202
 203         serial = sdi->conn;
 204         if (devc->state == IDLE) {
 205                 if (serial_read_nonblocking(serial, buf, 128) != 1 || buf[0] != 0x10)
 206                         /* Nothing there, or caught the tail end of a previous packet,
 207                          * or some garbage. Unless it's a single "data ready" byte,
 208                          * we don't want it. */
 209                         return TRUE;
 210                 /* Got 0x10, "measurement ready". */
 211                 delay_ms = serial_timeout(serial, 1);
 212                 if (serial_write_blocking(serial, "\x20", 1, delay_ms) < 1)
 213                         sr_err("unable to send command");
 214                 else {
 215                         devc->state = COMMAND_SENT;
 216                         devc->buflen = 0;
 217                 }
 218         } else {
 219                 len = serial_read_nonblocking(serial, devc->buf + devc->buflen,
 220                                 10 - devc->buflen);
 221                 if (len < 1)
 222                         return TRUE;
 223                 devc->buflen += len;
 224                 if (devc->buflen > 10) {
 225                         sr_dbg("buffer overrun");
 226                         devc->state = IDLE;
 227                         return TRUE;
 228                 }
 229                 if (devc->buflen == 10) {
 230                         /* If we got here, we're sure the device sent a "data ready"
 231                          * notification, we asked for data, and got it. */
 232                         process_packet(sdi);
 233                         devc->state = IDLE;
 234                 }
 235         }
 236
 237         return TRUE;
 238 }