Preparations for LOI continue. I was involved briefly when the burn-related Absolute-Time [command] Sequence (ATS) was "committed" to EEPROM in the onboard computer. The LOI burn will be controlled by an onboard command sequence, just as the Mid-Course Correction was. ("Absolute-time" refers to the commands being executed at specific times, for example, the burn start will be commanded at 09:47:18 Universal Time on Day 174 of 2009.)
The reason for committing the ATS to EEPROM is in case the computer should experience an unexpected reset (like booting a home computer) before LOI begins. In that case, we can recover more quickly if the ATS has been stored in EEPROM, the contents of which survive resets. We can then copy the ATS into RAM (where our executable code and data reside), rather than having to re-upload it from the ground. It gives us an extra (though small) margin of saved time in case of emergency.
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