1-3. Circuit Operation
1-3-1. DVA-M1100
BF-77 board 1-bit serial signal and 27 MHz clock signal that are supplied from the DVA-MC1100 at the TTL level are buffered by the BF-77 board and are sent to IC181 of the MB-75 board via TP185 and TP186 of the MB-75 board.
1-3-2. DVA-MC1100
IF-747 board MPU (IC3) communicates with the DVA-M1100 via the remote connector (CN2) using RS-232C. It controls the HDD that is connected to the SCSI connector (CN3) via the SCSI controller (IC12) and reads data from the HDD. DMA (IC8) writes data that is read from the SCSI connector, into DRAM (IC11). It also reads data from DRAM and converts the data from parallel to serial in synchronization with the 27 MHz clock. The IF-747 board sends the converted 1-bit serial signal to the DVA-M1100 together with the 27 MHz clock signal via the remote connector (CN2) at the TTL level.
