]> sigrok.org Git - libsigrok.git/blame_incremental - output/vcd.c
vcd: Fix output for more than 8 channels.
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1/*
2 * This file is part of the libsigrok project.
3 *
4 * Copyright (C) 2010 Uwe Hermann <uwe@hermann-uwe.de>
5 * Copyright (C) 2013 Bert Vermeulen <bert@biot.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22#include <stdlib.h>
23#include <string.h>
24#include <glib.h>
25#include "config.h" /* Needed for PACKAGE and others. */
26#include "libsigrok.h"
27#include "libsigrok-internal.h"
28
29#define LOG_PREFIX "output/vcd"
30
31struct context {
32 int num_enabled_probes;
33 GArray *probeindices;
34 GString *header;
35 uint8_t *prevsample;
36 int period;
37 uint64_t samplerate;
38 uint64_t samplecount;
39 unsigned int unitsize;
40};
41
42static const char *vcd_header_comment = "\
43$comment\n Acquisition with %d/%d probes at %s\n$end\n";
44
45static int init(struct sr_output *o)
46{
47 struct context *ctx;
48 struct sr_probe *probe;
49 GSList *l;
50 GVariant *gvar;
51 int num_probes, i;
52 char *samplerate_s, *frequency_s, *timestamp;
53 time_t t;
54
55 if (!(ctx = g_try_malloc0(sizeof(struct context)))) {
56 sr_err("%s: ctx malloc failed", __func__);
57 return SR_ERR_MALLOC;
58 }
59
60 o->internal = ctx;
61 ctx->num_enabled_probes = 0;
62 ctx->probeindices = g_array_new(FALSE, FALSE, sizeof(int));
63
64 for (l = o->sdi->probes; l; l = l->next) {
65 probe = l->data;
66 if (probe->type != SR_PROBE_LOGIC)
67 continue;
68 if (!probe->enabled)
69 continue;
70 ctx->probeindices = g_array_append_val(
71 ctx->probeindices, probe->index);
72 ctx->num_enabled_probes++;
73 }
74 if (ctx->num_enabled_probes > 94) {
75 sr_err("VCD only supports 94 probes.");
76 return SR_ERR;
77 }
78
79 ctx->unitsize = (ctx->num_enabled_probes + 7) / 8;
80 ctx->header = g_string_sized_new(512);
81 num_probes = g_slist_length(o->sdi->probes);
82
83 /* timestamp */
84 t = time(NULL);
85 timestamp = g_strdup(ctime(&t));
86 timestamp[strlen(timestamp)-1] = 0;
87 g_string_printf(ctx->header, "$date %s $end\n", timestamp);
88 g_free(timestamp);
89
90 /* generator */
91 g_string_append_printf(ctx->header, "$version %s %s $end\n",
92 PACKAGE, PACKAGE_VERSION);
93
94 if (sr_config_get(o->sdi->driver, o->sdi, NULL, SR_CONF_SAMPLERATE,
95 &gvar) == SR_OK) {
96 ctx->samplerate = g_variant_get_uint64(gvar);
97 g_variant_unref(gvar);
98 if (!((samplerate_s = sr_samplerate_string(ctx->samplerate)))) {
99 g_string_free(ctx->header, TRUE);
100 g_free(ctx);
101 return SR_ERR;
102 }
103 g_string_append_printf(ctx->header, vcd_header_comment,
104 ctx->num_enabled_probes, num_probes, samplerate_s);
105 g_free(samplerate_s);
106 }
107
108 /* timescale */
109 /* VCD can only handle 1/10/100 (s - fs), so scale up first */
110 if (ctx->samplerate > SR_MHZ(1))
111 ctx->period = SR_GHZ(1);
112 else if (ctx->samplerate > SR_KHZ(1))
113 ctx->period = SR_MHZ(1);
114 else
115 ctx->period = SR_KHZ(1);
116 if (!(frequency_s = sr_period_string(ctx->period))) {
117 g_string_free(ctx->header, TRUE);
118 g_free(ctx);
119 return SR_ERR;
120 }
121 g_string_append_printf(ctx->header, "$timescale %s $end\n", frequency_s);
122 g_free(frequency_s);
123
124 /* scope */
125 g_string_append_printf(ctx->header, "$scope module %s $end\n", PACKAGE);
126
127 /* Wires / channels */
128 for (i = 0, l = o->sdi->probes; l; l = l->next, i++) {
129 probe = l->data;
130 if (probe->type != SR_PROBE_LOGIC)
131 continue;
132 if (!probe->enabled)
133 continue;
134 g_string_append_printf(ctx->header, "$var wire 1 %c %s $end\n",
135 (char)('!' + i), probe->name);
136 }
137
138 g_string_append(ctx->header, "$upscope $end\n"
139 "$enddefinitions $end\n$dumpvars\n");
140
141 if (!(ctx->prevsample = g_try_malloc0(ctx->unitsize))) {
142 g_string_free(ctx->header, TRUE);
143 g_free(ctx);
144 sr_err("%s: ctx->prevsample malloc failed", __func__);
145 return SR_ERR_MALLOC;
146 }
147
148 return SR_OK;
149}
150
151static int receive(struct sr_output *o, const struct sr_dev_inst *sdi,
152 const struct sr_datafeed_packet *packet, GString **out)
153{
154 const struct sr_datafeed_logic *logic;
155 struct context *ctx;
156 unsigned int i;
157 int p, curbit, prevbit, index;
158 uint8_t *sample;
159
160 (void)sdi;
161
162 *out = NULL;
163 if (!o || !o->internal)
164 return SR_ERR_ARG;
165 ctx = o->internal;
166
167 if (packet->type == SR_DF_END) {
168 *out = g_string_new("$dumpoff\n$end\n");
169 return SR_OK;
170 } else if (packet->type != SR_DF_LOGIC)
171 return SR_OK;
172
173 if (ctx->header) {
174 /* The header is still here, this must be the first packet. */
175 *out = ctx->header;
176 ctx->header = NULL;
177 ctx->samplecount = 0;
178 } else {
179 *out = g_string_sized_new(512);
180 }
181
182 logic = packet->payload;
183 for (i = 0; i <= logic->length - logic->unitsize; i += logic->unitsize) {
184 sample = logic->data + i;
185
186 for (p = 0; p < ctx->num_enabled_probes; p++) {
187 index = g_array_index(ctx->probeindices, int, p);
188 curbit = ((unsigned)sample[index / 8] >> (index % 8)) & 1;
189 prevbit = ((unsigned)ctx->prevsample[index / 8] >> (index % 8)) & 1;
190
191 /* VCD only contains deltas/changes of signals. */
192 if (prevbit == curbit && ctx->samplecount > 0)
193 continue;
194
195 /* Output which signal changed to which value. */
196 g_string_append_printf(*out, "#%.0f\n%i%c\n",
197 (double)ctx->samplecount / ctx->samplerate * ctx->period,
198 curbit, (char)('!' + p));
199 }
200
201 ctx->samplecount++;
202 memcpy(ctx->prevsample, sample, ctx->unitsize);
203 }
204
205 return SR_OK;
206}
207
208static int cleanup(struct sr_output *o)
209{
210 struct context *ctx;
211
212 if (!o || !o->internal)
213 return SR_ERR_ARG;
214
215 ctx = o->internal;
216 g_free(ctx);
217
218 return SR_OK;
219}
220
221struct sr_output_format output_vcd = {
222 .id = "vcd",
223 .description = "Value Change Dump (VCD)",
224 .df_type = SR_DF_LOGIC,
225 .init = init,
226 .receive = receive,
227 .cleanup = cleanup,
228};