Programming Method for Non-Destructive Verification of an External RAM Without Requiring That Contents of RAM Be Copied to Other Memory
Original Publication Date: 1985-May-01
Included in the Prior Art Database: 2005-Feb-18
Verification of an external RAM (random-access memory) is achieved without affecting the contents of the RAM. Address lines to the RAM are verified without copying large blocks of RAM data to temporary storage. This has utilization, for example, when a machine, which has battery back up to the RAM to store user and status information, for example, is powered on so that a check of the RAM insures proper machine operation. A flow chart of a routine shows complete verification of a RAM including address lines with only three temporary storage locations exterior of the RAM being required. The first memory location is defined as the location corresponding to all 0's on the address lines to the RAM with its contents being stored in TEMP1.