Functions
int	pg2sdr_set_lna_gain (pg2sdr_device *dev, unsigned gain)
	Set LNA stage gain step.

int	pg2sdr_set_mix_gain (pg2sdr_device *dev, unsigned gain)
	Set MIX stage gain step.

int	pg2sdr_set_vga_gain (pg2sdr_device *dev, unsigned gain)
	Set VGA stage gain step.

int	pg2sdr_get_stage_gains (pg2sdr_device dev, unsigned lna, unsigned mix, unsigned vga)
	Get per-stage gain step settings.

int	pg2sdr_set_lna_gain_db (pg2sdr_device *dev, double gain_db)
	Set LNA stage gain in dB.

int	pg2sdr_set_mix_gain_db (pg2sdr_device *dev, double gain_db)
	Set MIX stage gain in dB.

int	pg2sdr_set_vga_gain_db (pg2sdr_device *dev, double gain_db)
	Set VGA stage gain in dB.

int	pg2sdr_get_stage_gains_db (pg2sdr_device dev, double lna_db, double mix_db, double vga_db)
	Get per-stage gain settings in dB.

int	pg2sdr_set_total_gain_db (pg2sdr_device *dev, double gain_db)
	Set total gain, in dB.

int	pg2sdr_get_total_gain_db (pg2sdr_device dev, double gain_db)
	Get total gain setting, in dB.

Detailed Description

The tuner on PG2SDR hardware has three controllable gain-stages. In order, starting from the RF input, these stages are LNA, MIX, and VGA. Each stage has a configurable gain setting that can be set to one of 16 possible gain steps.

libpg2sdr provides three types of API for setting the gain of these stages, and matching getters to retrieve gain:

Total gain setting across all stages, in dB: pg2sdr_set_total_gain_db(), pg2sdr_get_total_gain_db(). This uses a precomputed table to convert between total gain and combined stage gains. This is the API you probably want to use unless you have special requirements.
Gain setting per stage, in terms of dB: pg2sdr_set_lna_gain_db(), pg2sdr_set_mix_gain_db(), pg2sdr_set_vga_gain_db(), pg2sdr_get_stage_gains_db(). This API operates in terms of approximate gain in dB per stage, using a calibration table to convert between dB and hardware gain steps.
Direct control of hardware gain step settings: pg2sdr_set_lna_gain(), pg2sdr_set_mix_gain(), pg2sdr_set_vga_gain(), pg2sdr_get_stage_gains(). This is a low-level API that works in terms of hardware gain steps, which do not directly correspond to any particular amplification ratio.

The gain APIs that deal in terms of dB rely on a set of gain tables, which provide conversions between hardware gain steps and values in dB. libpg2sdr provides a built-in set of tables by default. The conversion tables can be inspected or updated via pg2sdr_get_gain_tables() and pg2sdr_set_gain_tables().

All of the gain APIs can be called while streaming data, and take effect immediately when called.

Function Documentation

◆ pg2sdr_get_stage_gains()

int pg2sdr_get_stage_gains	(	pg2sdr_device *	dev,
		unsigned *	lna,
		unsigned *	mix,
		unsigned *	vga
	)

Get per-stage gain step settings.

This retrieves current hardware gain settings, in terms of the low-level hardware gain step for each stage.

Parameters

[in]	dev	the device to query
[out]	lna	if not NULL, location to store the current LNA gain step
[out]	mix	if not NULL, location to store the current MIX gain step
[out]	vga	if not NULL, location to store the current VGA gain step

Return values

PG2SDR_SUCCESS	success
PG2SDR_ERROR_BAD_ARGUMENT	if all of `lna`, `mix`, `vga` are NULL
<0	negative error code on failure

See also: pg2sdr_set_lna_gain(); pg2sdr_set_mix_gain(); pg2sdr_set_vga_gain()

◆ pg2sdr_get_stage_gains_db()

int pg2sdr_get_stage_gains_db	(	pg2sdr_device *	dev,
		double *	lna_db,
		double *	mix_db,
		double *	vga_db
	)

Get per-stage gain settings in dB.

This retrieves current hardware gain settings, converting hardware gain step settings to a gain in dB using the currently set gain table.

Parameters

[in]	dev	the device to query
[out]	lna_db	if not NULL, location to store the current LNA gain
[out]	mix_db	if not NULL, location to store the current MIX gain
[out]	vga_db	if not NULL, location to store the current VGA gain

Return values

PG2SDR_SUCCESS	success
PG2SDR_ERROR_BAD_ARGUMENT	if all of `lna_db`, `mix_db`, `vga_db` are NULL
<0	negative error code on failure

See also: pg2sdr_set_lna_gain_db(); pg2sdr_set_mix_gain_db(); pg2sdr_set_vga_gain_db(); pg2sdr_get_gain_tables()

◆ pg2sdr_get_total_gain_db()

int pg2sdr_get_total_gain_db	(	pg2sdr_device *	dev,
		double *	gain_db
	)

Get total gain setting, in dB.

This retrieves current hardware gain settings, and converts them to a total gain value in dB using the currently set gain table.

If the current gain was set by calling pg2sdr_set_total_gain_db() then the returned gain reflects the recorded gain setting for the entry in the gain table that was used. If the current gain was set by setting individual gain stages, then an estimated total gain is returned by looking at the gain table for each stage individually; this estimated total may not exactly match the total gain measurements in the gain table.

Parameters

[in]	dev	the device to query
[out]	gain_db	location to store the current total gain, in dB

Return values

PG2SDR_SUCCESS	success
PG2SDR_ERROR_BAD_ARGUMENT	if `gain_db` is NULL
<0	negative error code on failure

See also: pg2sdr_set_total_gain_db(); pg2sdr_get_gain_tables()

◆ pg2sdr_set_lna_gain()

int pg2sdr_set_lna_gain	(	pg2sdr_device *	dev,
		unsigned	gain
	)

Set LNA stage gain step.

Parameters

[in]	dev	the device to configure
[in]	gain	the LNA gain step to set, in the range [0..15]

Return values

PG2SDR_SUCCESS	success
PG2SDR_ERROR_BAD_ARGUMENT	`gain` is out of range
<0	negative error code on failure

See also: pg2sdr_get_stage_gains()

◆ pg2sdr_set_lna_gain_db()

int pg2sdr_set_lna_gain_db	(	pg2sdr_device *	dev,
		double	gain_db
	)

Set LNA stage gain in dB.

The requested dB value will be converted to a hardware gain step using the currently set gain table. The actual dB value may not exactly match the requested value.

Parameters

[in]	dev	the device to configure
[in]	gain_db	the LNA gain to set, in dB

Return values

PG2SDR_SUCCESS	success
<0	negative error code on failure

See also: pg2sdr_get_stage_gains_db(); pg2sdr_set_gain_tables()

◆ pg2sdr_set_mix_gain()

int pg2sdr_set_mix_gain	(	pg2sdr_device *	dev,
		unsigned	gain
	)

Set MIX stage gain step.

Parameters

[in]	dev	the device to configure
[in]	gain	the MIX gain step to set, in the range [0..15]

Return values

PG2SDR_SUCCESS	success
PG2SDR_ERROR_BAD_ARGUMENT	`gain` is out of range
<0	negative error code on failure

See also: pg2sdr_get_stage_gains()

◆ pg2sdr_set_mix_gain_db()

int pg2sdr_set_mix_gain_db	(	pg2sdr_device *	dev,
		double	gain_db
	)

Set MIX stage gain in dB.

The requested dB value will be converted to a hardware gain step using the currently set gain table. The actual dB value may not exactly match the requested value.

Parameters

[in]	dev	the device to configure
[in]	gain_db	the MIX gain to set, in dB

Return values

PG2SDR_SUCCESS	success
<0	negative error code on failure

See also: pg2sdr_get_stage_gains_db(); pg2sdr_set_gain_tables()

◆ pg2sdr_set_total_gain_db()

int pg2sdr_set_total_gain_db	(	pg2sdr_device *	dev,
		double	gain_db
	)

Set total gain, in dB.

The requested dB value is converted to a set of hardware gain steps for each stage, using the currently set gain table. The actual dB value may not exactly match the requested value.

Parameters

[in]	dev	the device to configure
[in]	gain_db	the total gain to set, in dB

Return values

PG2SDR_SUCCESS	success
<0	negative error code on failure

See also: pg2sdr_get_total_gain_db(); pg2sdr_set_gain_tables()

◆ pg2sdr_set_vga_gain()

int pg2sdr_set_vga_gain	(	pg2sdr_device *	dev,
		unsigned	gain
	)

Set VGA stage gain step.

Parameters

[in]	dev	the device to configure
[in]	gain	the VGA gain step to set, in the range [0..15]

Return values

PG2SDR_SUCCESS	success
PG2SDR_ERROR_BAD_ARGUMENT	`gain` is out of range
<0	negative error code on failure

See also: pg2sdr_get_stage_gains()

◆ pg2sdr_set_vga_gain_db()

int pg2sdr_set_vga_gain_db	(	pg2sdr_device *	dev,
		double	gain_db
	)

Set VGA stage gain in dB.

The requested dB value will be converted to a hardware gain step using the currently set gain table. The actual dB value may not exactly match the requested value.

Parameters

[in]	dev	the device to configure
[in]	gain_db	the VGA gain to set, in dB

Return values

PG2SDR_SUCCESS	success
<0	negative error code on failure

See also: pg2sdr_get_stage_gains_db(); pg2sdr_set_gain_tables()

Functions

Detailed Description

Function Documentation

◆ pg2sdr_get_stage_gains()

◆ pg2sdr_get_stage_gains_db()

◆ pg2sdr_get_total_gain_db()

◆ pg2sdr_set_lna_gain()

◆ pg2sdr_set_lna_gain_db()

◆ pg2sdr_set_mix_gain()

◆ pg2sdr_set_mix_gain_db()

◆ pg2sdr_set_total_gain_db()

◆ pg2sdr_set_vga_gain()

◆ pg2sdr_set_vga_gain_db()