Philips CD-I - Page 92

1.4. RS-232C interface.
This interface is fully compatible with RS-232C
standard.
- Connector
Type D-sub 25 pin connector: Male type
- Pin assignment
No. Name
I/0
1
FGND
2
TXD-
0
3
RXD-
I
4
RTS 0
5 CTS I
6
DSR
I
7
SGND
8 DCD
I
9
10
11
12
13
- Internal registers
Read
Address Register
No.
14
15
16
17
18
19
20
21
22
23
24
25
Note
Name
DTR
RI
I/0
0
I
340001
MR1A,MR2A mode register A
340003
SRA
status register A
340005
reserved
340007 RHRA RX holding register A
340009
IPCR
input port change register
34000B ISR input status register
34000D CTU counter/timer upper
34000F CTL counter/timer lower
340011
MR1B,MR2B
mode register B
340013
SRB status register B
340015
reserved
340017 RHRB RX holding register
B
340019 IVR interrupt vector register
34001B
input port
34001D start counter COimnand
34001F start counter c0Dm1and
7-12
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