What kind of computer is in the Rover and Lander?
The rover computer board uses an Intel 80C85 CPU that has been radiation hardened for class – S space flight applications. The 80C85 uses a multiplexed address/data bus with an 8-bit address bus and an 8-bit data bus. It runs on between 3 to 6 volts and has been designed to have a low power consumption. The rover has a total of 672 KBytes of memory, 160 Kbytes of which are non-volatile EEPROM. Of its total non-volatile memory, 48 KBytes is radiation hardened to protect it from SEU (Single Event Upset) latchups or damage. Not suprisingly, the code for the computer OS (Operating System) is stored in this area of memory. There is no hard disk in the rover for storing images or data, which are typically stored in a local buffer before being transmitted to the lander for downlink back to Earth. The CPU runs at a mind blowing speed of 2 MHz (0.1 MIPS – Million Instructions Per Second), which is significantly slower that many personal computers in use today. The source programs for the rover
