Datasheet

Chapter 23 DQ256 Port Integration Module (S12XDQ256PIMV2)
MC9S12XDP512 Data Sheet, Rev. 2.21
934 Freescale Semiconductor
23.0.5.23 Port S Data Register (PTS)
Read: Anytime.
Write: Anytime.
Port S pins 7–4 are associated with the SPI0. The SPI0 pin configuration is determined by several status
bits in the SPI0 module. Refer to SPI section for details. When not used with the SPI0, these pins can be
used as general purpose I/O.
Port S bits 3–0 are associated with the SCI1 and SCI0. The SCI ports associated with transmit pins 3 and
1 are configured as outputs if the transmitter is enabled. The SCI ports associated with receive pins 2 and
0 are configured as inputs if the receiver is enabled. Refer to SCI section for details. When not used with
the SCI, these pins can be used as general purpose I/O.
If the data direction bits of the associated I/O pins are set to logic level “1”, a read returns the value of the
port register, otherwise the buffered pin input state is read.
23.0.5.24 Port S Input Register (PTIS)
Table 23-26. PPST Field Descriptions
Field Description
7–0
PPST[7:0]
Pull Select Port T
0 A pull-up device is connected to the associated port T pin, if enabled by the associated bit in register PERT
and if the port is used as input.
1 A pull-down device is connected to the associated port T pin, if enabled by the associated bit in register PERT
and if the port is used as input.
76543210
R
PTS7 PTS6 PTS5 PTS4 PTS3 PTS2 PTS1 PTS0
W
SCI/SPI SS0 SCK0 MOSI0 MISO0 TXD1 RXD1 TXD0 RXD0
Reset 00000000
Figure 23-25. Port S Data Register (PTS)
76543210
R PTIS7 PTIS6 PTIS5 PTIS4 PTIS3 PTIS2 PTIS1 PTIS0
W
Reset
1
1. These registers are reset to zero. Two bus clock cycles after reset release the register values are updated with the
associated pin values.
————————
= Unimplemented or Reserved
Figure 23-26. Port S Input Register (PTIS)