Shared data lines for memory write and memory test operations

摘要

The present invention is embodied in a method and apparatus which permits the testing of a memory device by utilizing normally unused data write lines to conduct the results of the memory test operations to a memory controller or processor. The data read from a specific memory cell is input into a comparator through a data sense amplifier and compared to the data from another memory cell. When the data is not coincident, a switch is enabled causing a data write line to change states. The change of state of the data write line disables a buffer, causing it to output a tri-state signal. A controller detects and interprets the tri-state signal output from the buffer as improper memory functioning.