The arm_status data structure reports data describing the current status of the slow-control system. Data reported include the operating voltage (SiPM-3000), temperatures and more.
For arm_status there are seven 'register' and 'field' data in use. All register data are 32-bit floats (float32).
arm_status registers and fields — slow control and operation |
Register number and field name | Description |
AS0: op_voltage | Current operating voltage (SiPM only) |
AS1: voltage_target | Computed target voltage from request (directly or with correction applied) |
AS2: set_voltage | Current operating voltage set by the DAC (so that op_voltage matches req_volt (directly or with correction applied; SiPM only)) |
AS3: cpu_temperature | Current ARM M0+ processor core temperature |
AS4: x_temperature | Current temperature measured by the external temperature sensor at the PMT or SiPM. |
AS5: avg_temperature | Current temperature average (from selected sensor) |
AS6: dg_target | Target digital gain (reserved) |
AS7: led_target | Computed LED value target, for systems with LED. |
AS8: wall_clock_time | wall_clock time; Resolution is 65536/48MHz=1.365ms when wall_clock_time < 224; ie 22906 s |
AS9: op_status | Bitfield, operation status; cf user table below |
AS10: supply_voltage | Measured USB supply voltage |
AS11: fpga_count | Number of FPGA reboots since power on |
AS12: led_value | Measured LED value from FPGA, for systems with an LED. |
AS13: dc_offset | DC-offset in mV (90<DC<130) |
AS14: anode_current | PMT or SiPM DC anode current. |
The arm_status registers concerning slow control and operation.
There is only one higher-level 'user' dictionary entry for arm_status operation.
arm_status registers and fields — sample − background measurement: count rates and analysis |
Register number and field name | Description |
AS27: count_rate_diff | Sample − Background count rate |
AS28: count_rate_diff_err | Difference count rate 2-σ error computed using Poisson statistics. |
AS29: bck_probability | Probability that the sample count rate is caused by the measured background rate. |
AS30: bck_low_probability | Most alarmist: P(counts > N+sigma(N) | mu-sigma(mu)) |
AS31: bck_high_probability | Most cautious: P(counts > N-sigma(N) | mu+sigma(mu)) |
AS32: alarm_time | Alarm count down until alarm turns off when alarm_time = 0_seconds |
The arm_status registers concerning measuring sample − background and the statistical analysis.