| 摘要 |
<p>PURPOSE:To accurately test the operation of a data RAM by connecting to an output register one of or both of the X, Y-bus to supply the read data from a data RAM to an arithmetic operation circuit, etc. CONSTITUTION:In case of an operation of reading from the data RAM, after the setting of the page and the address of the data RAM from which the data is read out to an X-pointer XP and a RAM-pointer RPA or an RPB, function signals F0-F3 are inputted to make a read/write signal R/W in a high level, and further, after the designating of a read action, a chip selecting signal CS is made in low level. Accordingly, the data in a specified address of the data RAM is read out, transferred through the X-bus, and outputted to data signal lines D0-D15 via a multiplexer MPX and an output register OR. In such a way, the operation test of the data RAM is made accurate and efficient, and the transmission-throughput in case of DMA transmission is improved.</p> |
