diff --git a/hardware/hantek-dso/api.c b/hardware/hantek-dso/api.c index c9310336..5701f4d5 100644 --- a/hardware/hantek-dso/api.c +++ b/hardware/hantek-dso/api.c @@ -544,35 +544,19 @@ static int hw_dev_config_set(int dev_index, int hwcap, const void *value) return ret; } -/* Called by libusb (as triggered by handle_event()) when a transfer comes in. - * Only channel data comes in asynchronously, and all transfers for this are - * queued up beforehand, so this just needs so chuck the incoming data onto - * the libsigrok session bus. - */ -static void receive_transfer(struct libusb_transfer *transfer) +static void send_chunk(struct context *ctx, unsigned char *buf, + int num_samples) { struct sr_datafeed_packet packet; struct sr_datafeed_analog analog; - struct context *ctx; float ch1, ch2, range; int num_probes, data_offset, i; - ctx = transfer->user_data; - sr_dbg("hantek-dso: receive_transfer(): status %d received %d bytes", - transfer->status, transfer->actual_length); - - if (transfer->actual_length == 0) - /* Nothing to send to the bus. */ - return; - - ctx->current_transfer += transfer->actual_length; - sr_dbg("hantek-dso: got %d of %d in frame", ctx->current_transfer, ctx->framesize * 2); - num_probes = (ctx->ch1_enabled && ctx->ch2_enabled) ? 2 : 1; packet.type = SR_DF_ANALOG; packet.payload = &analog; /* TODO: support for 5xxx series 9-bit samples */ - analog.num_samples = transfer->actual_length / 2; + analog.num_samples = num_samples; analog.mq = SR_MQ_VOLTAGE; analog.unit = SR_UNIT_VOLT; analog.data = g_try_malloc(analog.num_samples * sizeof(float) * num_probes); @@ -590,24 +574,100 @@ static void receive_transfer(struct libusb_transfer *transfer) /* TODO: support for 5xxx series 9-bit samples */ if (ctx->ch1_enabled) { range = ((float)vdivs[ctx->voltage_ch1].p / vdivs[ctx->voltage_ch1].q) * 8; - ch1 = range / 255 * *(transfer->buffer + i * 2 + 1); + ch1 = range / 255 * *(buf + i * 2 + 1); /* Value is centered around 0V. */ ch1 -= range / 2; analog.data[data_offset++] = ch1; } if (ctx->ch2_enabled) { range = ((float)vdivs[ctx->voltage_ch2].p / vdivs[ctx->voltage_ch2].q) * 8; - ch2 = range / 255 * *(transfer->buffer + i * 2); + ch2 = range / 255 * *(buf + i * 2); ch2 -= range / 2; analog.data[data_offset++] = ch2; } } - g_free(transfer->buffer); - libusb_free_transfer(transfer); sr_session_send(ctx->cb_data, &packet); - if (ctx->current_transfer >= ctx->framesize * 2) { - /* That's the last chunk in this frame. */ +} + +/* Called by libusb (as triggered by handle_event()) when a transfer comes in. + * Only channel data comes in asynchronously, and all transfers for this are + * queued up beforehand, so this just needs so chuck the incoming data onto + * the libsigrok session bus. + */ +static void receive_transfer(struct libusb_transfer *transfer) +{ + struct sr_datafeed_packet packet; + struct context *ctx; + int num_samples, pre; + + ctx = transfer->user_data; + sr_dbg("hantek-dso: receive_transfer(): status %d received %d bytes", + transfer->status, transfer->actual_length); + + if (transfer->actual_length == 0) + /* Nothing to send to the bus. */ + return; + + num_samples = transfer->actual_length / 2; + + sr_dbg("hantek-dso: got %d-%d/%d samples in frame", ctx->samp_received + 1, + ctx->samp_received + num_samples, ctx->framesize); + + /* The device always sends a full frame, but the beginning of the frame + * doesn't represent the trigger point. The offset at which the trigger + * happened came in with the capture state, so we need to start sending + * from there up the session bus. The samples in the frame buffer before + * that trigger point came after the end of the device's frame buffer was + * reached, and it wrapped around to overwrite up until the trigger point. + */ + if (ctx->samp_received < ctx->trigger_offset) { + /* Trigger point not yet reached. */ + if (ctx->samp_received + num_samples < ctx->trigger_offset) { + /* The entire chunk is before the trigger point. */ + memcpy(ctx->framebuf + ctx->samp_buffered * 2, + transfer->buffer, num_samples * 2); + ctx->samp_buffered += num_samples; + } else { + /* This chunk hits or overruns the trigger point. + * Store the part before the trigger fired, and + * send the rest up to the session bus. */ + pre = ctx->trigger_offset - ctx->samp_received; + memcpy(ctx->framebuf + ctx->samp_buffered * 2, + transfer->buffer, pre * 2); + ctx->samp_buffered += pre; + + /* The rest of this chunk starts with the trigger point. */ + sr_dbg("hantek-dso: reached trigger point, %d samples buffered", + ctx->samp_buffered); + + /* Avoid the corner case where the chunk ended at + * exactly the trigger point. */ + if (num_samples > pre) + send_chunk(ctx, transfer->buffer + pre * 2, + num_samples - pre); + } + } else { + /* Already past the trigger point, just send it all out. */ + send_chunk(ctx, transfer->buffer, + num_samples); + } + + ctx->samp_received += num_samples; + + /* Everything in this transfer was either copied to the buffer or + * sent to the session bus. */ + g_free(transfer->buffer); + libusb_free_transfer(transfer); + + if (ctx->samp_received >= ctx->framesize) { + /* That was the last chunk in this frame. Send the buffered + * pre-trigger samples out now, in one big chunk. */ + sr_dbg("hantek-dso: end of frame, sending %d pre-trigger buffered samples", + ctx->samp_buffered); + send_chunk(ctx, ctx->framebuf, ctx->samp_buffered); + + /* Mark the end of this frame. */ packet.type = SR_DF_FRAME_END; sr_session_send(ctx->cb_data, &packet); @@ -617,7 +677,6 @@ static void receive_transfer(struct libusb_transfer *transfer) packet.type = SR_DF_END; sr_session_send(ctx->cb_data, &packet); } else { - ctx->current_transfer = 0; ctx->dev_state = NEW_CAPTURE; } } @@ -629,6 +688,7 @@ static int handle_event(int fd, int revents, void *cb_data) struct sr_datafeed_packet packet; struct timeval tv; struct context *ctx; + int num_probes; uint32_t trigger_offset; uint8_t capturestate; @@ -678,6 +738,13 @@ static int handle_event(int fd, int revents, void *cb_data) /* no data yet */ break; case CAPTURE_READY_8BIT: + /* Remember where in the captured frame the trigger is. */ + ctx->trigger_offset = trigger_offset; + + num_probes = (ctx->ch1_enabled && ctx->ch2_enabled) ? 2 : 1; + ctx->framebuf = g_try_malloc(ctx->framesize * num_probes * 2); + ctx->samp_buffered = ctx->samp_received = 0; + /* Tell the scope to send us the first frame. */ if (dso_get_channeldata(ctx, receive_transfer) != SR_OK) break; diff --git a/hardware/hantek-dso/dso.c b/hardware/hantek-dso/dso.c index 75832c8a..e9d74dfb 100644 --- a/hardware/hantek-dso/dso.c +++ b/hardware/hantek-dso/dso.c @@ -672,7 +672,7 @@ SR_PRIV int dso_get_capturestate(struct context *ctx, uint8_t *capturestate, */ bitvalue = 1; for (i = 0; i < 24; i++) { - // Each set bit inverts all bits with a lower value + /* Each set bit inverts all bits with a lower value. */ if(toff & bitvalue) toff ^= bitvalue - 1; bitvalue <<= 1; diff --git a/hardware/hantek-dso/dso.h b/hardware/hantek-dso/dso.h index ac260147..e21be0ee 100644 --- a/hardware/hantek-dso/dso.h +++ b/hardware/hantek-dso/dso.h @@ -173,9 +173,9 @@ struct context { GTimeVal fw_updated; int epin_maxpacketsize; int capture_empty_count; - int current_transfer; int dev_state; + /* Oscilloscope settings. */ int timebase; gboolean ch1_enabled; gboolean ch2_enabled; @@ -188,7 +188,7 @@ struct context { float voffset_ch2; float voffset_trigger; uint16_t channel_levels[2][9][2]; - int framesize; + unsigned int framesize; gboolean filter_ch1; gboolean filter_ch2; gboolean filter_trigger; @@ -196,6 +196,12 @@ struct context { char *triggersource; float triggerposition; int triggermode; + + /* Frame transfer */ + unsigned int samp_received; + unsigned int samp_buffered; + unsigned int trigger_offset; + unsigned char *framebuf; }; SR_PRIV int dso_open(int dev_index);