6
3V
3V
3V3V
3V3V
3V
3V3V
3V
3V
3V
CPU
CPU
CPU CPU
CMOS CMOS
CMOS CMOS
RXD
DCD-
DSR-
RI-
CTS-
TXD
DTR-
RTS-
MSGWAIT-
INRANGE-
LOWBATT- SENSE1-4
TxDA RxDA
INDICATE SENSE
PWRON CPU
RESET-
INTERFACE CIRCUIT OF CNI-800D
27 27
10K
10K
330K
10K
10K
27
HOST HOST
HOST
HOST
HOST
