Datasheet

Infrared Serial Communications
Technical Data MC68HC908LJ12 — Rev. 2.1
250 Infrared Serial Communications Interface Module (IRSCI) Freescale Semiconductor
Table 13-5 shows a summary of I/O pin functions when the SCI is
enabled.
13.11 I/O Registers
The following I/O registers control and monitor SCI operation:
• SCI control register 1 (SCC1)
• SCI control register 2 (SCC2)
• SCI control register 3 (SCC3)
• SCI status register 1 (SCS1)
• SCI status register 2 (SCS2)
• SCI data register (SCDR)
• SCI baud rate register (SCBR)
• SCI infrared control register (SCIRCR)
Table 13-5. SCI Pin Functions (Standard and Infrared)
SCC1
[ENSCI]
SCIRCR
[IREN]
SCC2
[TE]
SCC2
[RE]
TxD Pin RxD Pin
1000
Hi-Z
(1)
Input ignored (terminate externally)
1001
Hi-Z
(1)
Input sampled, pin should idle high
1 0 1 0 Output SCI (idle high) Input ignored (terminate externally)
1 0 1 1 Output SCI (idle high) Input sampled, pin should idle high
1100
Hi-Z
(1)
Input ignored (terminate externally)
1101
Hi-Z
(1)
Input sampled, pin should idle high
1 1 1 0 Output IR SCI (idle high) Input ignored (terminate externally)
1 1 1 1 Output IR SCI (idle high) Input sampled, pin should idle high
0 X X X Pins under port control (standard I/O port)
Notes:
1. After completion of transmission in progress.