correct discrepancy between number of samples and number of bytes in …

…blocks of samples

related to greatscottgadgets#346

firmware/hackrf_usb/usb_api_sweep.c

@@ -47,11 +47,11 @@ static enum sweep_style style = LINEAR;
 usb_request_status_t usb_vendor_request_init_sweep(
 		usb_endpoint_t* const endpoint, const usb_transfer_stage_t stage)
 {
-	uint32_t num_samples;
+	uint32_t num_bytes;
 	int i;
 	if (stage == USB_TRANSFER_STAGE_SETUP) {
-		num_samples = (endpoint->setup.index << 16) | endpoint->setup.value;
-		dwell_blocks = num_samples / 0x4000;
+		num_bytes = (endpoint->setup.index << 16) | endpoint->setup.value;
+		dwell_blocks = num_bytes / 0x4000;
 		if(1 > dwell_blocks) {
 			return USB_REQUEST_STATUS_STALL;
 		}

host/hackrf-tools/src/hackrf_sweep.c

@@ -98,7 +98,7 @@ int gettimeofday(struct timeval *tv, void* ignored) {
 #define TUNE_STEP (DEFAULT_SAMPLE_RATE_HZ / FREQ_ONE_MHZ)
 #define OFFSET 7500000
 
-#define DEFAULT_SAMPLE_COUNT 0x4000
+#define DEFAULT_SAMPLE_COUNT 0x2000
 #define BLOCKS_PER_TRANSFER 16
 
 #if defined _WIN32
@@ -219,23 +219,23 @@ int rx_callback(hackrf_transfer* transfer) {
 					| ((uint64_t)(ubuf[6]) << 32) | ((uint64_t)(ubuf[5]) << 24) | ((uint64_t)(ubuf[4]) << 16)
 					| ((uint64_t)(ubuf[3]) << 8) | ubuf[2];
 		} else {
-			buf += SAMPLES_PER_BLOCK;
+			buf += BYTES_PER_BLOCK;
 			continue;
 		}
 		if(!sweep_started) {
 			if (frequency == (uint64_t)(FREQ_ONE_MHZ*frequencies[0])) {
 				sweep_started = true;
 			} else {
-				buf += SAMPLES_PER_BLOCK;
+				buf += BYTES_PER_BLOCK;
 				continue;
 			}
 		}
 		if((FREQ_MAX_MHZ * FREQ_ONE_MHZ) < frequency) {
-			buf += SAMPLES_PER_BLOCK;
+			buf += BYTES_PER_BLOCK;
 			continue;
 		}
 		/* copy to fftwIn as floats */
-		buf += SAMPLES_PER_BLOCK - (fftSize * 2);
+		buf += BYTES_PER_BLOCK - (fftSize * 2);
 		for(i=0; i < fftSize; i++) {
 			fftwIn[i][0] = buf[i*2] * window[i] * 1.0f / 128.0f;
 			fftwIn[i][1] = buf[i*2+1] * window[i] * 1.0f / 128.0f;
@@ -304,7 +304,7 @@ static void usage() {
 	fprintf(stderr, "\t[-p antenna_enable] # Antenna port power, 1=Enable, 0=Disable\n");
 	fprintf(stderr, "\t[-l gain_db] # RX LNA (IF) gain, 0-40dB, 8dB steps\n");
 	fprintf(stderr, "\t[-g gain_db] # RX VGA (baseband) gain, 0-62dB, 2dB steps\n");
-	fprintf(stderr, "\t[-n num_samples] # Number of samples per frequency, 16384-4294967296\n");
+	fprintf(stderr, "\t[-n num_samples] # Number of samples per frequency, 8192-4294967296\n");
 	fprintf(stderr, "\t[-w bin_width] # FFT bin width (frequency resolution) in Hz\n");
 	fprintf(stderr, "\t[-1] # one shot mode\n");
 	fprintf(stderr, "\t[-B] # binary output\n");
@@ -447,12 +447,12 @@ int main(int argc, char** argv) {
 		fprintf(stderr, "warning: vga_gain (-g) must be a multiple of 2\n");
 
 	if (num_samples % SAMPLES_PER_BLOCK) {
-		fprintf(stderr, "warning: num_samples (-n) must be a multiple of 16384\n");
+		fprintf(stderr, "warning: num_samples (-n) must be a multiple of 8192\n");
 		return EXIT_FAILURE;
 	}
 
 	if (num_samples < SAMPLES_PER_BLOCK) {
-		fprintf(stderr, "warning: num_samples (-n) must be at least 16384\n");
+		fprintf(stderr, "warning: num_samples (-n) must be at least 8192\n");
 		return EXIT_FAILURE;
 	}
 
@@ -592,7 +592,7 @@ int main(int argc, char** argv) {
 				frequencies[2*i], frequencies[2*i+1]);
 	}
 
-	result = hackrf_init_sweep(device, frequencies, num_ranges, num_samples,
+	result = hackrf_init_sweep(device, frequencies, num_ranges, num_samples * 2,
 			TUNE_STEP * FREQ_ONE_MHZ, OFFSET, INTERLEAVED);
 	if( result != HACKRF_SUCCESS ) {
 		fprintf(stderr, "hackrf_init_sweep() failed: %s (%d)\n",

host/libhackrf/src/hackrf.c

@@ -1811,7 +1811,7 @@ int ADDCALL hackrf_set_hw_sync_mode(hackrf_device* device, const uint8_t value)
  * Initialize sweep mode:
  * frequency_list is a list of start/stop pairs of frequencies in MHz.
  * num_ranges is the number of pairs in frequency_list (1 to 10)
- * num_samples is the number of samples to capture after each tuning.
+ * num_bytes is the number of sample bytes to capture after each tuning.
  * step_width is the width in Hz of the tuning step.
  * offset is a number of Hz added to every tuning frequency.
  *     Use to select center frequency based on the expected usable bandwidth.
@@ -1823,7 +1823,7 @@ int ADDCALL hackrf_set_hw_sync_mode(hackrf_device* device, const uint8_t value)
  */
 int ADDCALL hackrf_init_sweep(hackrf_device* device,
 		const uint16_t* frequency_list, const int num_ranges,
-		const uint32_t num_samples, const uint32_t step_width,
+		const uint32_t num_bytes, const uint32_t step_width,
 		const uint32_t offset, const enum sweep_style style) {
 	USB_API_REQUIRED(device, 0x0102)
 	int result, i;
@@ -1834,11 +1834,11 @@ int ADDCALL hackrf_init_sweep(hackrf_device* device,
 		return HACKRF_ERROR_INVALID_PARAM;
 	}
 
-	if(num_samples % SAMPLES_PER_BLOCK) {
+	if(num_bytes % BYTES_PER_BLOCK) {
 		return HACKRF_ERROR_INVALID_PARAM;
 	}
 
-	if(SAMPLES_PER_BLOCK > num_samples) {
+	if(BYTES_PER_BLOCK > num_bytes) {
 		return HACKRF_ERROR_INVALID_PARAM;
 	}
 
@@ -1868,8 +1868,8 @@ int ADDCALL hackrf_init_sweep(hackrf_device* device,
 		device->usb_device,
 		LIBUSB_ENDPOINT_OUT | LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE,
 		HACKRF_VENDOR_REQUEST_INIT_SWEEP,
-		num_samples & 0xffff,
-		(num_samples >> 16) & 0xffff,
+		num_bytes & 0xffff,
+		(num_bytes >> 16) & 0xffff,
 		data,
 		size,
 		0

host/libhackrf/src/hackrf.h

@@ -47,7 +47,8 @@ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSI
 
 #endif
 
-#define SAMPLES_PER_BLOCK 16384
+#define SAMPLES_PER_BLOCK 8192
+#define BYTES_PER_BLOCK 16384
 #define MAX_SWEEP_RANGES 10
 
 enum hackrf_error {
@@ -229,7 +230,7 @@ extern ADDAPI int ADDCALL hackrf_set_hw_sync_mode(hackrf_device* device, const u
 /* Start sweep mode */
 extern ADDAPI int ADDCALL hackrf_init_sweep(hackrf_device* device,
 		const uint16_t* frequency_list, const int num_ranges,
-		const uint32_t num_samples, const uint32_t step_width,
+		const uint32_t num_bytes, const uint32_t step_width,
 		const uint32_t offset, const enum sweep_style style);
 
 /* Operacake functions */