Overview
Just Add Power models with stereo output ports can distribute audio to an analog audio distribution system. The stereo output on some models includes adjustable audio delay and volume control. Delay and volume can be adjusted through push-buttons on the bottom of the devices or through programming.
AVP Transmitters (and KVM Transmitters with the Dolby upgrade) have two additional audio input ports - mic input and line input - for embedding additional analog audio sources onto the HDMI signal. Control of the three audio signals - HDMI, mic, line - allows each signal to be turned on and off independently.
ST1 Sound Transceivers are audio-only endpoints in a Just Add Power system that can act as either an audio input or an audio output. They can be part of 2G and 3G systems.
Stereo Audio Delay
Some models with a stereo output port have the ability to delay the analog audio signal to match with a digital video signal.
Compatible Models
- 218AVP
- 418AVP
- 515POE
- 518AVP
- 715POE
- 718AVP
- 718KVM (with Dolby upgrade)
- 725POE
- 749AVP
- 749KVM (with Dolby upgrade)
Audio Delay Commands
Audio delay ranges from 0 ms (milliseconds) to 175 ms. Default is 0 ms.
All commands are case-sensitive. Variables are represented by $X. A6.x.x commands will work on justOS firmwares as well. justOS commands will NOT work on A6.x.x firmware.
| Firmware A6.x.x | ||||
|---|---|---|---|---|
| Name | Command | Variable Options | Example | Description |
| Read Current Delay | AUD_DLY_READ_CURRENT | (none) | AUD_DLY_READ_CURRENT |
Read the current audio delay value on the device (0 to 25) |
| Increase Delay | AUD_DLY_SLOW $X |
0 to 25 | AUD_DLY_SLOW 4 |
Increase delay compared to current value by 7ms * value (28 in example) |
| Decrease Delay | AUD_DLY_FAST $X |
0 to 25 | AUD_DLY_FAST 6 |
Decrease delay compared to current value by 7ms * value (42 in example) |
| Set Delay | AUD_DLY_SET_VALUE $X |
0 to 25 | AUD_DLY_SLOW 12 |
Set delay to 7ms * value (84 in example) |
| Save Delay Value | AUD_DLY_SAVE_VAL | (none) | AUD_DLY_SAVE_VAL |
Save the current delay value to persist through reboot |
| justOS Firmware Bx.x.x | ||||
|---|---|---|---|---|
| Name | Command | Variable Options | Example | Description |
| Set Delay | POST /command/audio/stereo/delay $X |
0 to 175 | POST /command/audio/stereo/delay 175 |
Set delay to the value (175ms in example) |
| Save Delay Value | (none) | (none) | (none) | Setting the delay automatically saves |
Stereo Audio Volume
Models with a stereo output port can make minor adjustments to the volume level of the analog output.
Compatible Models
- 218AVP
- 418AVP
- 518AVP
- 718AVP
- 718KVM (with Dolby upgrade)
- 749AVP
- 749KVM (with Dolby upgrade)
Volume Commands
Volume adjustment ranges from -39dB to +6dB. Default is 0dB.
All commands are case-sensitive. Variables are represented by $X. A6.x.x commands will work on justOS firmwares as well. justOS commands will NOT work on A6.x.x firmware.
| Firmware A6.x.x | ||||
|---|---|---|---|---|
| Name | Command | Variable Options | Example | Description |
| Increase Volume | vol_bth_up.sh | (none) | vol_bth_up.sh |
Increase volume compared to current value (1-31) |
| Decrease Volume | vol_bth_dn.sh | (none) | vol_bth_dn.sh |
Decrease volume compared to current value (1-31) |
| Set Volume | vol_bth_set.sh $X |
1 (-39dB) to 31 (+6dB) in 1.5dB increments | vol_bth_set.sh 31 |
Set volume to 31 (+6dB) |
| Mute Stereo Port | vol_mute.sh | (none) | vol_mute.sh |
Mutes the stereo port. Persists until unmuted. |
| Unmute Stereo Port | vol_unmute.sh | (none) | vol_unmute.sh |
Unmutes the stereo port. Volume returns to previous level. |
| justOS Firmwares Bx.x.x | ||||
|---|---|---|---|---|
| Name | Command | Variable Options | Example | Description |
| Set Volume | POST /command/audio/stereo/volume $X |
0 (-39dB) to 11 (+6dB) in 5-6dB increments | POST /command/audio/stereo/volume 10 |
Set volume. 10 is HDMI-level |
Mic & Line Inputs
AVP Transmitters have two additional audio inputs: mic-input and line-input. The audio inputs are distributed over the network and are available to all Receivers watching that Transmitter.
Input Commands
HDMI, mic, and line audio inputs are enabled by default.
All commands are case-sensitive. Variables are represented by $X. A6.x.x commands will work on justOS firmwares as well. justOS commands will NOT work on A6.x.x firmware.
| Firmware A6.x.x | ||||
|---|---|---|---|---|
| Name | Command | Variable Options | Example | Description |
| Enable HDMI Audio | dd_main_on.sh | (none) | dd_main_on.sh |
Enable audio transmission for HDMI input signal |
| Disable HDMI Audio | dd_main_mute.sh | (none) | dd_main_mute.sh |
Disable audio transmission for HDMI input signal |
| Enable Line Audio | dd_line_on.sh | (none) | dd_line_on.sh |
Enable the Line input port |
| Disable Line Audio | dd_line_mute.sh | (none) | dd_line_mute.sh |
Disable the Line input port |
| Enable Mic Audio | dd_mic_on.sh | (none) | dd_mic_on.sh |
Enable the Mic input port |
| Disable Mic Audio | dd_mic_mute.sh | (none) | dd_mic_mute.sh |
Disable the Mic input port |
The commands below for justOS only set the live status, and will not affect the on-boot status for the devices.
For the on-boot Settings commands, head to the 3G Device Settings article in the Audio section.
| justOS Firmwares Bx.x.x | ||||
|---|---|---|---|---|
| Name | Command | Variable Options | Example | Description |
| Enable/Disable HDMI Audio | POST /command/audio/dsp/hdmi $X |
mute, on |
POST /command/audio/dsp/hdmi mute |
Set audio status for HDMI input signal (on or mute) |
| Enable/Disable Line Audio | POST /command/audio/dsp/line $X |
mute, on |
POST /command/audio/dsp/line mute |
Set audio status for Line input port (on or mute) |
| Enable/Disable Mic Audio | POST /command/audio/dsp/mic $X |
mute, on |
POST /command/audio/dsp/mic mute |
Set audio status for Mic input port (on or mute) |
ST1 Transceiver
Volume Commands - justOS Firmware
Volume adjustment ranges from -46dB to +12dB, broken up into 11 steps for the command.
| Command value | dB |
|---|---|
| 1 | -46.5 dB |
| 2 | -42 dB |
| 3 | -36 dB |
| 4 | -30 dB |
| 5 | -24 dB |
| 6 | -18 dB |
| 7 | -12 dB |
| 8 | -6 dB |
| 9 | 0 dB |
| 10 | +6 dB |
| 11 | +12 dB |
All commands are case-sensitive. Variables are represented by $X. justOS commands will NOT work on A6.x.x firmware.
| Transmitter or Receiver Mode | ||||
|---|---|---|---|---|
| Name | Command | Variable Options | Example | Description |
| Set Live Volume | POST /command/audio/stereo/volume $X | integer 0-11 | POST /command/audio/stereo/volume 11 |
Set live volume level from 0-11. Does not persist through reboot. |
| Read Live Volume | GET /details/audio/stereo/volume | (none) | GET /details/audio/stereo/volume |
Check the current volume level setting |
| Set Boot-Up Volume | POST /settings/audio/stereo/volume $X | integer 0-11 | POST /settings/audio/stereo/volume 11 |
Set the volume level when the unit boots up |
| Read Boot-Up Volume | GET /settings/audio/stereo/volume | (none) | GET /settings/audio/stereo/volumel |
Check the volume level the unit will be set to when booting up |
Volume Commands - Hybrid Firmware
All commands are case-sensitive. Variables are represented by $X. A6.x.x commands will work on justOS firmwares as well.
| Transmitter Mode | ||||
|---|---|---|---|---|
| Name | Command | Variable Options | Example | Description |
| Set Live Volume | echo $X > /sys/devices/platform/1500_i2s/analog_in_vol | integer 0-100 | echo 100 > /sys/devices/platform/1500_i2s/analog_in_vol |
Set live volume level from 0-100. Does not persist through reboot. |
| Read Live Volume | cat /sys/devices/platform/1500_i2s/analog_in_vol | (none) | cat /sys/devices/platform/1500_i2s/analog_in_vol |
Check the current volume level setting |
| Set Boot-Up Volume | astparam s analog_in_val $X | integer 0-100 | astparam s analog_in_val 100 |
Set the volume level when the unit boots up |
| Read Boot-Up Volume | astparam g analog_in_val | (none) | astparam g analog_in_val |
Check the volume level the unit will be set to when booting up |
| Receiver Mode | ||||
|---|---|---|---|---|
| Name | Command | Variable Options | Example | Description |
| Set Live Volume | echo $X > /sys/devices/platform/1500_i2s/analog_out_vol | integer 0-100 | echo 100 > /sys/devices/platform/1500_i2s/analog_out_vol |
Set live volume level from 0-100. Does not persist through reboot. |
| Read Live Volume | cat /sys/devices/platform/1500_i2s/analog_out_vol | (none) | cat /sys/devices/platform/1500_i2s/analog_out_vol |
Check the current volume level setting |
| Set Boot-Up Volume | astparam s analog_out_val $X | integer 0-100 | astparam s analog_out_val 100 |
Set the volume level when the unit boots up |
| Read Boot-Up Volume | astparam g analog_out_val | (none) | astparam g analog_out_val |
Check the volume level the unit will be set to when booting up |
