ECOM 721: Table 3

Table 3

Summery of Commands

BBRC Command Number	Mnemonic	BBRC Bilevel Number	Bilevel	State	Remarks
R 4330 4331	HV1 pwr on off	71-21	HV1 pwr	1 0	Turns on/off high voltage supply1, change can also be noted on HVMON. Transmit R4330 only when +28 bus is on.
4332 4333	HV1 msb hi lo	71-22	HV1 msb	1 0	Selects programming resistors which control the output of HV supply 1.
4334 4335	HV1 lsb hi lo	71-23	HV1 lsb	1 0	Change can also be noted on HVMON.
4336 4337	DISCR 1 hi lo	71-24	DISCR 1	1 0	Selects level of PPA 1's pulse amplitude discriminator.
4338 4339	DSS 1 A B	71-25	DSS 1	0 1	Selects channel A/B as data source for PPA 1.
R4350 4351	HV2 pwr on off	71-26	HV2 pwr	1 0	Turns on/off high voltage supply 2, change can also be noted on HVMON. Transmit R4350 only when +28 bus is on.
4352 4353	HV2 msb hi lo	71-27	HV MSB	1	Selects programming resistors which control the output of HV supply 2.
4354 4355	HV2 lsb hi lo	71-28	HV1 lsb	1	Change can also be noted on HVMON.
4356 4357	DISCR 2 hi lo	71-29	DISCR 2	1 0	Selects level of PPA 2's pulse amplitude discriminator.
4358 4359	DSS 2 A B	71-30	DSS 2	0 1	Selects channel A/B as data source for PPA 2.
R4370 R4371	LVS A B	71-31	LVS	0 1	Selects primary/backup low voltage power supply for experiment electronics. Transmit only when +28V bus is off.
4313 4312	RESOL 10 A 5 A	71-32	RESOL	0 1	Selects 5/10 Angstrom resolution mode of the memory.
4314 4315	HRES PPA 1 PPA 2	71-33	HRES PPA	1 0	Selects PPA 1/2 as data sources when memory is in 5 angstrom resolution mode. Also selects PPA 1/2 as data source when ECOM is in SERIAL data mode.
R4310 4311	PHOTOM on off	71-34	PHOTOM	1 0	Turns on/off the photometer.
In addition, the following five commands have no bilevel monitors
4318	GRATING STEP	--	--	--	Connects +28V bus 2 to a Ledex 36-step continuous rotation stepping motor. T/M verification is by noting a change in the GRATING analog monitor.
4302 4303	MEMORY DATA SERIAL DATA	--	--	--	SCF Mode 30 SCF Mode 31 Selects source of 8-bit digital data to be either the TRW add-one memory, or the output of a PPA directly (as selected by the HRES PPA relay). Instead of a bilevel, the MEMORY/SERIAL flag to software is the state of the DSS 2 bilevels, see Table 4. SCF mode refers to the data processing and display mode at the Satellite Control Facility.
4316 4317	DET O'LOAD on off	--	--	--	Turns on/off the detector overload automatic shutdown function. If on and if the detector event rate exceeds 10200/sec, then the circuit will automatically turn off HV1 and/or HV2. The HV1 and/or HV2 bilevels will then be 0. After 255 seconds the HV supplies will automatically be turned back on. If this function is off, then there is no effect on the experiments functioning.
This final command is implemented by the spacecraft.
4300 4301	ECOM-721 on off	71-35	Ecom-721	1 0	Turns on/off +28V buses 1 and 2.