Sony DSC-D700 Service Manual page 100

. Card control block (IC002)
The control pulses (CA0-CA10, CWE (11), COE (10), CCE1 (8), and CCE2 (9))
for inputting and outputting data to a card are produced by a peripheral device
control circuit (IC002). The input/output data or control pulses are converted in
voltage level for input and output according to the supply voltage (5 V or 3.3 V)
of the PC card used.
. Real-time clock block (IC005)
The real-time clock circuit IC005 sets and acquires the clock information via serial
communication (CE (5), DATA (6), and CLK (7) signals of IC005) by main
microcomputer IC001.
The internal power supply of a circuit is switched to the backup battery (BAT981
on the IO-177 board) to store the internal data by the output signal of reset circuit
IC008 when the power is turned off.
The TIRQ (10) signal of IC005 is also used as a wake-up signal that is sent to the
key/LCD microcomputer (IC501 on the KC-47 board).
. Serial communication block (IC010)
IC010 is an RS-232C driver. IC010 is connected with the two-channel serial ports
(RXD0 and TXD0, and RXD1 and TXD1) of main microcomputer IC001 for
servicing or debugging. The resulting data is output to connector CN705 on the
IF-717 board.
4-12 DSC-D700 (UC,CE)