The 29C516E Atmel EDAC is a very low power flowthrough 16bit Error Detection And Correction unit (EDAC) with two user data buses. The EDAC is used in a high integrity system for monitoring and correction of data values coming from the memory space. During a processor write cycle, at each memory location (16bit width), EDAC calculated checkword (6 or 8bit width) is added. When performing a read operation from memory, the 29C516E verifies the entire checkword and data combination. It detects and can correct 100% of all the singlebit errors and it detects all doublebit errors. When the 29C516E uses 6checkbit, it can detect any error on any single 4bit memory chip. The 8checkbit option gives the additional capability to detect all errors on any single 8bit memory chip. All the errors are signaled to the master system (via 2 error Flags) in order to allow the processor to make the required action. The 29C516E operates in two possible modes: corrected or detected mode. In the corrected mode, the singlebit in error is complemented (corrected). Then, the available entire data is placed on the output port and the Correctable Error Flag is set. In case of doublebit errors (or more),