System: measurements¶
JP150PCB 1.3PCB 1.4generatedJan PřibyslavskýThis page does not apply to the product or PCB revision chosen in the header.
Supply voltage, current and power, and the temperatures of the MCU and of the power-stage heatsink with their minima and maxima since start. PCB 1.4 measures the supply with its INA226 power monitor, PCB 1.3 with the MCU's ADC.
Commands¶
| Command | Function | Parameter | Answer | Since | Boards |
|---|---|---|---|---|---|
SYS:MEAS:VOLT? |
Supply voltage in V | – | SYS:MEAS:VOLT:<volts> |
26.6.2 | 1.3, 1.4 |
SYS:MEAS:CURR? |
Supply current in A | – | SYS:MEAS:CURR:<amps> |
26.6.2 | 1.3, 1.4 |
SYS:MEAS:POW? |
Supply power in W | – | SYS:MEAS:POW:<watts> |
26.10.1 | 1.3, 1.4 |
SYS:MEAS:TEMP? |
MCU temperature in degrees C (short form) | – | SYS:MEAS:TEMP:<celsius> |
26.6.2 | 1.3, 1.4 |
SYS:MEAS:TEMP:MCU? † |
MCU temperature in degrees C | – | SYS:MEAS:TEMP:MCU:<celsius> |
26.6.2 | 1.3, 1.4 |
SYS:MEAS:TEMP:MCU:MIN? † |
Lowest MCU temperature read since start | – | SYS:MEAS:TEMP:MCU:MIN:<celsius> |
26.6.2 | 1.3, 1.4 |
SYS:MEAS:TEMP:MCU:MAX? † |
Highest MCU temperature read since start | – | SYS:MEAS:TEMP:MCU:MAX:<celsius> |
26.6.2 | 1.3, 1.4 |
SYS:MEAS:TEMP:PWRSTAGE? |
Power-stage heatsink temperature in degrees C | – | SYS:MEAS:TEMP:PWRSTAGE:<celsius> |
26.6.2 | 1.3, 1.4 |
SYS:MEAS:TEMP:PWRSTAGE:MIN? |
Lowest heatsink temperature read since start | – | SYS:MEAS:TEMP:PWRSTAGE:MIN:<celsius> |
26.6.2 | 1.3, 1.4 |
SYS:MEAS:TEMP:PWRSTAGE:MAX? |
Highest heatsink temperature read since start | – | SYS:MEAS:TEMP:PWRSTAGE:MAX:<celsius> |
26.6.2 | 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. †: also served in the safe state (see SYS:BOARD:TYPE?).
SYS:MEAS:VOLT?, SYS:MEAS:CURR?, SYS:MEAS:POW?¶
Commands: SYS:MEAS:VOLT?, SYS:MEAS:CURR?, SYS:MEAS:POW?
Two decimals each. On PCB 1.4 the three come from the INA226 power monitor: the voltage after
the inrush limiter and the shunt (slightly below the supply input, 0 to 36 V), the whole-board
current with 0.625 mA resolution, averaged, a new result about every 141 ms; when the monitor
cannot be read the queries draw no answer (an SCPI error). On PCB 1.3 the voltage comes from
the ADC and the current from the TMCS1108 sensor through the ADC with an 80 ms filter.
SYS:MEAS:POW? multiplies voltage and current of one reading; the product of separate
VOLT? and CURR? answers can differ while the load changes with the music.
SYS:MEAS:VOLT? -> SYS:MEAS:VOLT:24.50
SYS:MEAS:CURR? -> SYS:MEAS:CURR:1.25
SYS:MEAS:POW? -> SYS:MEAS:POW:30.63
MCU temperature¶
Commands: SYS:MEAS:TEMP?, SYS:MEAS:TEMP:MCU?, SYS:MEAS:TEMP:MCU:MIN?, SYS:MEAS:TEMP:MCU:MAX?
The temperature sensor inside the STM32; SYS:MEAS:TEMP? is the same value with a shorter
prefix, kept for compatibility. The minimum and maximum are the extremes of the readings taken
at query time: every MCU temperature query folds a fresh reading into them, nothing is sampled
between queries, and the values do not survive a restart.
Power-stage temperature¶
Commands: SYS:MEAS:TEMP:PWRSTAGE?, SYS:MEAS:TEMP:PWRSTAGE:MIN?, SYS:MEAS:TEMP:PWRSTAGE:MAX?
The TMP112 sensor on the power-stage heatsink, read over I2C on request (-40 to 125 degrees C). A missing sensor or a bus error is an SCPI error, never a made-up value. The minimum and maximum follow the same query-time rule as the MCU extremes and answer an SCPI error until the sensor has been read once.
Changes¶
- 26.10.1: added
SYS:MEAS:POW?. - 26.6.2 (oldest release documented): 9 commands.