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GALILEO

The Galileo Energetic Particles Detector

 

Galileo EPD Handbook

 

Chapter 1. Instrument Summary

 

Command Changes

 

Source: Stephen Jaskulek, October 2, 1987

 

 

Command Redefinition

 

A number of present EPD command functions will be altered by the proposed design changes. Below is a list of these commands.

 

TABLE 11. PROPOSED CHANGES TO PRESENT EPD COMMAND FUNCTIONS

 

Command Name State Hex Code Location New Name/Function
TOVR AN ON C2 PSB 4, bit 1 "PRIME ACTIVE"/ Prime An. (simult. mode) on
TOVR AN OFF C3 PSB 4, bit 1 "PRIME ACTIVE"/ Prime An. (simult. mode) off
TOVR RL ON AB PSB 2, bit 7 spare (TOF spectrum off ??)
TOVR RL OFF 8B PSB 2, bit 7 spare (TOF spectrum on ??)
TOF POWER ON B2 PSB 2, bit 4 TOF POWER/Still TOF Power (±6 Volt only)
TOF POWER OFF 92 PSB 2, bit 4 TOF POWER/Still TOF Power (±6 Volt only)
CMS L CHANNEL ON BA PSB 4, BIT 4 KT/Same function, but chan. now used for KT
CMS L CHANNEL OFF 9A PSB 4, BIT 4 KT/Same function, but chan. now used for KT
CMS JC CHANNEL ON B8 PSB 4, BIT 5 JB'/Same function, but chan. now used for Jb'
CMS JC CHANNEL OFF 98 PSB 4, BIT 5 JB'/Same function, but chan. now used for Jb'
CMS JB CHANNEL ON B7 PSB 4, BIT 6 KT0 SELECT/Selects low energy thrshld on KT0
CMS JB CHANNEL OFF 97 PSB 4, BIT 6 KT0 SELECT/Selects high energy thrshld on KT0
JA00 ENABLE ON BB PSB 4, BIT 3 HIGH VOLT. ENABLE/Switch ±15 Volt on to HV
JA00 ENABLE OFF 9B PSB 4, BIT 3 HIGH VOLT. ENABLE/Switch ±15 Volt off to HV

 

A number of present EPD command functions will be altered by the proposed design changes, in addition to new commands. Below is a list of the command changes. Note that initially more than one symbol can have a given hex code. For example, the ground support computer will generate the command code "C2"  if I send either the command "LCR" or "SM." Eventually, the old command symbols will be purged from the command table.

 

TABLE 12. PROPOSED CHANGES TO PRESENT EPD COMMAND DICTIONARY

 

Hex Code Old Symbol New Symbol New Field Description
C2 LCR SM Simultaneous mode ON ("PRIME ACTIVE" on)
C3 LC SMR Simultaneous mode OFF ("PRIME ACTIVE" on)
AB TRL TS spare (TOF Spectrum off ??)
8B TRLR TSR spare (TOF Spectrum on ??)
BA CL CKT CMS Analog Kt ON
9A CLR CKTR CMS Analog Kt  OFF
B8 CJC CJB CMS Analog Jc ON
98 CJCR CJBR CMS Analog Jc OFF
B7 -- KTL KT00 ON (Selects low energy thrshld on KT0)
97 -- KTLR KT00 OFF (Selects high energy thrshld on KT0)
BB -- HV HIGH VOLT. ENABLE (Switch ±15 volt on to HV)
9B -- HVR HIGH VOLT. DISABLE (Switch ±15 volt off to HV)
FA -- VIT VITO ON
FB -- VITR VITO OFF
FC -- HLIM SET HIGH VOLTAGE LIMIT
FD -- HREF SET HIGH VOLTAGE REFERENCE

 

 

Continue: New Commands

 

Return to the CMS Subsystem Index

Return to Galileo EPD Handbook Table of Contents Page.

Return to main Galileo Table of Contents Page.
Return to 
Fundamental Technologies Home Page.

 


Updated 8/23/19, Cameron Crane

QUICK FACTS

Manufacturer: The Galileo Spacecraft was manufactured by the Jet Propulsion Laboratory, Messerschmitt-Bölkow-Blohm, General Electric, and the Hughes Aircraft Company.

Mission Duration: Galileo was planned to have a mission duration of around 8 years, but was kept in operation for 13 years, 11 months, and 3 days, until it was destroyed in a controlled impact with Jupiter on September 21, 2003.

Destination: Galileo's destination was Jupiter and its moons, which it orbitted for 7 years, 9 months, and 13 days.