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Chapter 19 Port Integration Module (S12XFPIMV2)
MC9S12XF - Family Reference Manual, Rev.1.19
Freescale Semiconductor
871
19.3.37 Port M Data Register (PTM)
Address 0x0250
Access: User read/write(1)
1. Read: Anytime.
Write: Anytime.
76543210
R
PTM7
PTM6
PTM5
PTM4
PTM3
PTM2
PTM1
PTM0
W
Altern.
Function
SS1
SCK1
MOSI1
MISO1
FAULT3
FAULT2
TXCAN
RXCAN
CS3
CS2
CS1
CS0
Reset
00000000
Figure 19-35. Port M Data Register (PTM)
Table 19-33. PTM Register Field Descriptions
Field
Description
7
PTM
Port M general purpose input/output data—Data Register
Port M pin 7 is associated with the SS signal of the SPI1 module and the chip select output CS3. The SPI function
takes precedence over the chip select.
When not used with the alternative function, this pin can be used as general purpose I/O.
If the associated data direction bit of this pin is set to 1, a read returns the value of the port register, otherwise the
buffered pin input state is read.
6
PTM
Port M general purpose input/output data—Data Register
Port M pin 6 is associated with the SCK signal of the SPI1 module.
When not used with the alternative function, this pin can be used as general purpose I/O.
If the associated data direction bit of this pin is set to 1, a read returns the value of the port register, otherwise the
buffered pin input state is read.
5
PTM
Port M general purpose input/output data—Data Register
Port M pin 5 is associated with the MOSI signal of the SPI1 module.
When not used with the alternative function, this pin can be used as general purpose I/O.
If the associated data direction bit of this pin is set to 1, a read returns the value of the port register, otherwise the
buffered pin input state is read.
4
PTM
Port M general purpose input/output data—Data Register
Port M pin 4 is associated with the MISO signal of the SPI1 module and the chip select output CS2. The SPI function
takes precedence over the chip select.
When not used with the alternative function, this pin can be used as general purpose I/O.
If the associated data direction bit of this pin is set to 1, a read returns the value of the port register, otherwise the
buffered pin input state is read.
3-2
PTM
Port M general purpose input/output data—Data Register
Port M pins 3 and 2 are associated with the PMF fault inputs FAULT[3:2] and chip select outputs CS[1:0]. The PMF
function takes precedence over the chip selects. When not used with the alternative functions, these pins can be
used as general purpose I/O.
If the associated data direction bits of these pins are set to 1, a read returns the value of the port register, otherwise
the buffered pin input state is read.