| 摘要 |
PURPOSE:To detect address fault in writing and reading and fault in overwriting and overreading without increasing the number of bits of the storage circuit of an FIFO data buffer. CONSTITUTION:This data buffer has an EX-OR circuit 10 which EX-ORs the parity bit of write data with the parity bit of a write address register 1, a means which inputs the parity bit of the write data to the EX-OR circuit 10 and writes the write data and the output of the 1st EX-OR circuit 10 in a storage circuit 5, an EX-OR circuit 11 which EX-ORs the parity bit of the stored data with the parity bit of a read address register, and a means which adds the output of the EX-OR circuit 11 as a parity bit to the read storage data to generate read data; and the parity of the read data is checked. The fault of the data buffer can be detected by the conversion and reproduction of the input data by those EX-OR circuits 10 and 11. |
