Description
The Abort Guidance System included the following components:
- Abort Electronic Assembly (AEA): the computer
- Abort Sensor Assembly (ASA): a simple strapdown IMU
- Data Entry and Display Assembly (DEDA): the interface similar to DSKY
The computer used was MARCO 4418 (MARCO stands for Man Rated Computer) whose dimensions were 5 by 8 by 23,75 inches (12,7 by 20,3 by 60,33 centimeters); it weighed 32,7 pounds (14,83 kg) and required 90 watts of power. Because the memory had a serial access it was slower than AGC, although some operations on AEA were performed as fast or faster than on AGC.
The computer had the following characteristics:
- It had 4096 words of memory. Lower 2048 words were erasable memory (RAM), higher 2048 words served as fixed memory (ROM). The fixed and erasable memory were constructed similarly so the ratio between fixed and erasable memory was variable.
- It was an 18-bit machine, with 17 magnitude bits and a sign bit. The addresses were 13 bits long; MSB indicated index addressing.
- Data words were two's complement and in fixed-point form.
Read more about this topic: Apollo Abort Guidance System
Famous quotes containing the word description:
“A sound mind in a sound body, is a short, but full description of a happy state in this World: he that has these two, has little more to wish for; and he that wants either of them, will be little the better for anything else.”
—John Locke (1632–1704)
“I fancy it must be the quantity of animal food eaten by the English which renders their character insusceptible of civilisation. I suspect it is in their kitchens and not in their churches that their reformation must be worked, and that Missionaries of that description from [France] would avail more than those who should endeavor to tame them by precepts of religion or philosophy.”
—Thomas Jefferson (1743–1826)
“The type of fig leaf which each culture employs to cover its social taboos offers a twofold description of its morality. It reveals that certain unacknowledged behavior exists and it suggests the form that such behavior takes.”
—Freda Adler (b. 1934)