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5.2 Instrument Restart after a Power-Off

When a BEP is powered off (i.e. its corresponding power-supply side is turned off or is disabled), it loses its patch list. When the power is re-applied, the bad pixel and column maps, system configuration table, huffman table modifications, and all parameter blocks are overwritten by those stored in ROM.

The italicized checks may be performed out-of-sequence (i.e. not in real-time) if the hardware and the procedure have been thoroughly tested in-flight, and the spacecraft is not in ground contact when the power-on procedure needs to run.

5.2.1 Normal - BEP A and B powered, BEP A Selected

The normal use of the system is to have both BEP A and B powered, allowing use of all 6 FEPs, and BEP A as the selected BEP.

  1. If DPA Side-B is on, select B, power off FEPs, wait 10 seconds, select A (Section 3.1.2, Section 3.3.2)

  2. If DPA Side-B is off, enable DPA Side B, power on DPA Side B (Section 3.1.1)

  3. Power On DPA Side A (Section 3.1.1)

  4. Check Voltage, Current, and Thermal (Section 3.4.1)

  5. Check BEP Startup Message (Section 3.4.2)

  6. Re-load patch list (Section 3.7.1.1)

  7. Dump patch list and check (Section 3.6.2.4)

  8. Ensure the desired DEA side is on (Section 3.3.3)

  9. Warm Boot (Section 3.1.3.3)

  10. Check BEP Startup Message (look at version) (Section 3.4.2)

  11. Re-load System Configuration parameters (especially focal plane temperatures) (Section 3.3)

  12. Check Voltage, Current and Thermal since video boards and FEPs may be powered, and the focal plane temperature set-point will be modified (Section 3.4.1)

  13. Dump System Configuration table and check (Section 3.6.2.5)

  14. Re-load Bad Pixel and Column Maps (Section 3.5)

  15. Re-load static DEA, TE, CC, 2D, and 1D parameter blocks (i.e. those not automatically re-loaded at start of each run) (Section 3.4.6.1, Section 4.1.4)

  16. Dump Bad Pixel and Column maps, parameter block slots, and Huffman table and check (Section 3.6.2.1, Section 3.6.2.3, Section 3.6.2.2)

  17. Re-load Huffman table changes (if any) using Write-BEP commands (Section 3.7.2)

  18. Wait longer than 8 minutes after step 9 (1 minute to power on boards, and 7 minutes for FEP time-stamps to synchronize), where the FEP power may have been re-applied

  19. Start the first observation, ensuring that bias-maps are re-computed and telemetered (Section 4.1)

5.2.2 Contingency/Test - BEP A and B powered, BEP B Selected

One contingency or test scenario is to have both BEP A and B powered, allowing use of all 6 FEPs, but using BEP B as the selected BEP.

  1. If DPA Side-A is on, select A, power off FEPs, wait 10 seconds, hold reset A (Section 3.1.2, Section 3.3.2, Section 3.2.2)

  2. If DPA Side-A is off, enable DPA Side A, power on DPA Side A, hold reset A (Section 3.1.1, Section 3.2.2)

  3. Power On DPA Side B (reset A is still driving the interfaces, should see 0xb7 in software telemetry stream) (Section 3.1.1)

  4. Check Voltage, Current, and Thermal (Section 3.4.1 )

  5. Select BEP B (BEP B is now driving the interfaces, packets should appear) (Section 3.1.2)

  6. Check BEP Startup Message (Section 3.4.2)

  7. Re-load patch list (Section 3.7.1.1)

  8. Dump patch list and check (Section 3.6.2.4 )

  9. Ensure the desired DEA side is on (Section 3.3.3 )

  10. Warm Boot (Section 3.1.3.3)

  11. Check BEP Startup Message (look at version) (Section 3.4.2)

  12. Re-load System Configuration parameters (especially focal plane temperatures) (Section 3.3)

  13. Check Voltage, Current and Thermal since video boards and FEPs may be powered, and the focal plane temperature set-point will be modified (Section 3.4.1)

  14. Dump System Configuration table and check (Section 3.6.2.5)

  15. Re-load Bad Pixel and Column Maps (Section 3.5)

  16. Re-load Huffman table changes (if any) using BEP Write-Memory commands (Section 3.7.2)

  17. Re-load static DEA, TE, CC, 2D, and 1D parameter blocks (i.e. those not automatically re-loaded at start of each run) (Section 3.4.6.1, Section 4.1.4)

  18. Dump Bad Pixel and Column maps, parameter block slots, and Huffman table and check (Section 3.6.2.1, Section 3.6.2.3, Section 3.6.2.2)

  19. Wait longer than 8 minutes after step 9 (1 minute to power on boards, and 7 minutes for FEP time-stamps to synchronize), where the FEP power may have been re-applied

  20. Start the first observation, ensuring that bias-maps are re-computed and telemetered (Section 4.1)

5.2.3 Contingency/Test - Only BEP A powered

If BEP B fails in a manner that requires that it not be powered, such as a short on the board, only 3 of the 6 FEPs may be used, and only BEP A may be used.

  1. Power On DPA Side A (Section 3.1.1)

  2. Check Voltage, Current, and Thermal (Section 3.4.1)

  3. Check BEP Startup Message (Section 3.4.2)

  4. Re-load patch list (Section 3.7.1.1)

  5. Dump patch list and check (Section 3.6.2.4)

  6. Ensure the DPA Side-B is off (Section 3.2.1)

  7. Ensure the desired DEA side is on (Section 3.3.3)

  8. Warm Boot (Section 3.1.3.3)

  9. Check BEP Startup Message (look at version) (Section 3.4.2)

  10. Re-load System Configuration parameters (especially focal plane temperatures) WARNING: Ensure that only FEPs 0, 1 and 2 are powered. FEPs 3, 4 and 5 are powered by the Side-B DPA power supply (Section 3.3)

  11. Check Voltage, Current and Thermal since video boards and FEPs may be powered, and the focal plane temperature set-point will be modified (Section 3.4.1)

  12. Dump System Configuration table and check (Section 3.6.2.5)

  13. Re-load Bad Pixel and Column Maps (Section 3.5)

  14. Re-load Huffman table changes (if any) using BEP Write-Memory commands (Section 3.7.2)

  15. Re-load static DEA, TE, CC, 2D, and 1D parameter blocks (i.e. those not automatically re-loaded at start of each run) (Section 3.4.6.1, Section 4.1.4)

  16. Dump Bad Pixel and Column maps, parameter block slots and Huffman table and check (Section 3.6.2.1, Section 3.6.2.3, Section 3.6.2.2)

  17. Wait longer than 8 minutes after step 9 (1 minute to power on boards, and 7 minutes for FEP time-stamps to synchronize), where the FEP power may have been re-applied

  18. Start the first observation, ensuring that bias-maps are re-computed and telemetered. NOTE: FEPs 3, 4, and 5 cannot be used for science, since their corresponding power supply is off. Ensure that the primary CCDs of interest are configured for FEPs 0, 1, or 2. (Section 4.1)

5.2.4 Contingency/Test - Only BEP B powered

If BEP A fails in a manner that requires that it not be powered, such as a short on the board, only 3 of the 6 FEPs may be used, and only BEP B may be used.

  1. Ensure the desired DEA side is on (Section 3.3.3)

  2. Power On DPA Side B (no board will be driving the interface at this point) (Section 3.1.1)

  3. Check Voltage, Current, and Thermal (Section 3.4.1)

  4. Select BEP B (BEP will now start driving the interfaces) (Section 3.1.2)

  5. Check BEP Startup Message (Section 3.4.2)

  6. Re-load patch list (Section 3.7.1.1)

  7. Dump patch list and check (Section 3.6.2.4)

  8. Ensure the DPA Side-A is off (Section 3.2.1)

  9. Warm Boot (Section 3.1.3.3)

  10. Check BEP Startup Message (look at version) (Section 3.4.2)

  11. Re-load System Configuration parameters (especially focal plane temperatures) WARNING: Ensure that only FEPs 3, 4 and 5 are powered. FEPs 0, 1 and 2 are powered by the Side-A DPA power supply (Section 3.3)

  12. Check Voltage, Current and Thermal since video boards and FEPs may be powered, and the focal plane temperature set-point will be modified (Section 3.4.1)

  13. Dump System Configuration table and check (Section 3.6.2.5)

  14. Re-load Bad Pixel and Column Maps (Section 3.5)

  15. Re-load Huffman table changes (if any) using BEP Write-Memory commands (Section 3.7.2)

  16. Re-load static DEA, TE, CC, 2D, and 1D parameter blocks (i.e. those not automatically re-loaded at start of each run) (Section 3.4.6.1, Section 4.1.4)

  17. Dump Bad Pixel and Column maps, parameter block slots and Huffman table and check (Section 3.6.2.1, Section 3.6.2.3, Section 3.6.2.2)

  18. Wait longer than 8 minutes after step 9 (1 minute to power on boards, and 7 minutes for FEP time-stamps to synchronize), where the FEP power may have been re-applied

  19. Start the first observation, ensuring that bias-maps are re-computed and telemetered. NOTE: FEPs 0, 1, and 2 cannot be used for science, since their corresponding power supply is off. Ensure that the primary CCDs of interest are configured for FEPs 3, 4, or 5 (Section 4.1)

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James E. Francis
Last modified: Wed Jan 12 10:58:39 EST