System: power¶
JP150PCB 1.3PCB 1.4generatedJan PřibyslavskýThis page does not apply to the product or PCB revision chosen in the header.
The power levels of the module, the automatic power-down after a period of silence, and the USB-C power sense of PCB 1.4. The operation pages explain the levels from the owner's side.
Commands¶
| Command | Function | Parameter | Answer | Since | Boards |
|---|---|---|---|---|---|
SYS:POWER:MODE? |
Power level | – | SYS:POWER:MODE:<level> |
26.6.2 | 1.3, 1.4 |
SYS:POWER:MODE |
Set the power level | <level> |
no answer | 26.6.2 | 1.3, 1.4 |
SYS:POWER:USBC? |
USB-C power source present | – | SYS:POWER:USBC:<1|0|N/A> |
26.10.1 | 1.4 (1.3: N/A) |
SYS:POWER:AUTO? |
Automatic power-down enabled | – | SYS:POWER:AUTO:<0|1> |
26.6.2 | 1.3, 1.4 |
SYS:POWER:AUTO |
Enable or disable the automatic power-down | 0, 1 |
no answer | 26.6.2 | 1.3, 1.4 |
SYS:POWER:AUTO:MODE? |
Level entered after the silence delay | – | SYS:POWER:AUTO:MODE:<level> |
26.8.0 | 1.3, 1.4 |
SYS:POWER:AUTO:MODE |
Set the level entered after the silence delay | PWRSTAGE_IDLE, PWRSTAGE_OFF, SLEEP, STANDBY |
no answer | 26.8.0 | 1.3, 1.4 |
SYS:POWER:AUTO:DELAY? |
Silence delay in seconds | – | SYS:POWER:AUTO:DELAY:<seconds> |
26.8.0 | 1.3, 1.4 |
SYS:POWER:AUTO:DELAY |
Set the silence delay | 10..65535 |
no answer | 26.8.0 | 1.3, 1.4 |
SYS:POWER:AUTO:THRESHOLD? |
Level above which audio counts as present | – | SYS:POWER:AUTO:THRESHOLD:<raw> |
26.8.0 | 1.3, 1.4 |
SYS:POWER:AUTO:THRESHOLD |
Set the silence threshold | <raw> |
no answer | 26.8.0 | 1.3, 1.4 |
SYS:POWER:AUTO:STATE? |
Automatic power-down status and countdown | – | SYS:POWER:AUTO:STATE:<enabled>,<armed>,<configured>,<effective>,<timeout_s>,<elapsed_s>,<remaining_s> |
26.8.0 | 1.3, 1.4 |
Since is the release the command appeared in; 26.6.2 is the oldest release documented here, so a command marked 26.6.2 may be older.
SYS:POWER:MODE¶
Commands: SYS:POWER:MODE?, SYS:POWER:MODE
Each level switches off one more part of the module than the previous one:
| Level | Power stages | 12 V rail | 5 V rail | DSP |
|---|---|---|---|---|
NORMAL |
on | on | on | running |
PWRSTAGE_IDLE |
muted, in reset | on | on | running |
PWRSTAGE_OFF |
muted, in reset | off | on | running |
SLEEP |
muted, in reset | off | on | in reset |
STANDBY |
muted, in reset | off | off | in reset |
The MCU keeps running and answering in every level. The level is not stored: the module
starts in NORMAL. Returning to NORMAL from PWRSTAGE_OFF, SLEEP or STANDBY
re-initialises the power stages before they are unmuted; the control interface waits for
about 350 ms plus that initialisation, so a host allows for it in its timeout. Leaving SLEEP
or STANDBY boots the DSP from its boot memory again, and the firmware re-applies the
selected input itself. In STANDBY the Wi-Fi module is unpowered: WIFI:* queries fail or
time out then, which is not a lost connection. Automatic power-down, the 12 V trigger and
audio wake change the level without a command; SYS:POWER:AUTO:STATE? and SYS:TRIG? show
why.
Power levels
| Value | Meaning |
|---|---|
NORMAL |
Everything on |
PWRSTAGE_IDLE |
The power stages are muted and held in reset; their 12 V supply stays on |
PWRSTAGE_OFF |
As PWRSTAGE_IDLE, and the 12 V supply of the power stages is off |
SLEEP |
As PWRSTAGE_OFF, and the DSP is held in reset. The 5 V rail, and with it the Wi-Fi module, stays powered |
STANDBY |
As SLEEP, and the 5 V rail is off, so the Wi-Fi module is unpowered. The MCU keeps running and answering |
SYS:POWER:USBC?¶
1 while the USB-C power-delivery controller of PCB 1.4 is powered, that is while a USB-C
source is connected. A report only; the firmware does not act on it. N/A on PCB 1.3.
SYS:POWER:AUTO¶
Commands: SYS:POWER:AUTO?, SYS:POWER:AUTO
The master switch of the automatic power-down after silence. Off by default; a stored setting. A value above 1 is an SCPI error.
Default: 0.
SYS:POWER:AUTO:MODE¶
Commands: SYS:POWER:AUTO:MODE?, SYS:POWER:AUTO:MODE
NORMAL is refused with an SCPI error: it is the level being left. The setting is a
preference: the level actually entered is limited at the moment of the transition, for example
to SLEEP while Wi-Fi is the selected input, because the Wi-Fi module must stay powered to
wake the module on audio. SYS:POWER:AUTO:STATE? reports both the configured and the
effective level. A stored setting.
Default: PWRSTAGE_OFF.
SYS:POWER:AUTO:DELAY¶
Commands: SYS:POWER:AUTO:DELAY?, SYS:POWER:AUTO:DELAY
Whole seconds of continuous silence before the module powers down. Values below 10 s are refused: shorter than that, the module could power down in a gap between tracks. A stored setting.
Default: 1800.
SYS:POWER:AUTO:THRESHOLD¶
Commands: SYS:POWER:AUTO:THRESHOLD?, SYS:POWER:AUTO:THRESHOLD
The threshold is in the raw units of DSP:LVLMETER:RMS? (Q8.24: 16777216 is full scale), not
in dB; dBFS = 20 log10(raw / 16777216). The meter sits before the volume, so the threshold
is a source-level one, unaffected by volume or mute. The default of 5 (about -130 dBFS) is near
the floor on purpose: every input is digital, a stopped stream reads exactly 0 and anything
playing clears 5 by orders of magnitude. Residuals in the DSP chain (dither, a DC offset, a
decaying RMS detector) also count as audio and postpone the power-down; raise the threshold if
the module does not power down. Reference points: 11879 is -63 dBFS (the bottom LED of the
level meter), 2112126 is -18 dBFS (loud programme material). 0 means nothing ever counts as
silence; a value above 16777216 would make everything count as silence, so that the module
powers down during playback and cannot wake on audio. MuraLink refuses such values; the command
itself does not. A stored setting.
Default: 5.
SYS:POWER:AUTO:STATE?¶
Everything a host needs to show a countdown: enabled mirrors SYS:POWER:AUTO?; armed is
1 while silence is being counted, that is enabled and in NORMAL; configured and
effective are the set and the limited target level; then the delay, the silence so far and
the remaining seconds. The elapsed time restarts at 0 on every level change, so a wake always
gets the full delay. With armed 0 the last two fields mean nothing.
Changes¶
- 26.10.1: added
SYS:POWER:USBC?. - 26.8.0: added
SYS:POWER:AUTO:MODE?,SYS:POWER:AUTO:MODE,SYS:POWER:AUTO:DELAY?,SYS:POWER:AUTO:DELAY,SYS:POWER:AUTO:THRESHOLD?,SYS:POWER:AUTO:THRESHOLD,SYS:POWER:AUTO:STATE?. - 26.6.2 (oldest release documented): 4 commands.