Freescale Semiconductor MPC5604B - Page 352

MPC5604B/C Microcontroller Reference Manual, Rev. 8
Freescale Semiconductor 341
19.5.3.9 Pad Selection for Multiplexed Inputs Registers (PSMI0_3–PSMI28_31)
In some cases, a peripheral input signal can be selected from more than one pin. For example, the
CAN1_RXD signal can be selected on three different pins: PC[3], PC[11] and PF[15]. Only one can be
active at a time. To select the pad to be used as input to the peripheral:
• Select the signal via the pad’s PCR register using the PA field.
• Specify the pad to be used via the appropriate PSMI field.
In order to multiplex different pads to the same peripheral input, the SIUL provides a register that controls
the selection between the different sources.
Offsets:0x0500–0x051C (8 registers) Access: User read/write
0123456789101112131415
R0000
PADSEL0
0000
PADSEL1
W
Reset0000000000000000
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
R0000
PADSEL2
0000
PADSEL3
W
Reset0000000000000000
Figure 19-10. Pad Selection for Multiplexed Inputs Register (PSMI0_3)
Table 19-12. PSMI0_3 field descriptions
Field Description
PADSEL0–3,
PADSEL4–7,
...
PADSEL28–31
Pad Selection Bits
Each PADSEL field selects the pad currently used for a certain input function. See Table 19-13.
Table 19-13. Peripheral input pin selection
PSMI registers PADSEL fields SIUL address offset Function / Peripheral Mapping
1
PSMI0_3 PADSEL0 0x500 CAN1RX / FlexCAN_1 00: PCR[35]
01: PCR[43]
10: PCR[95]
2
PADSEL1 0x501 CAN2RX / FlexCAN_2 00: PCR[73]
01: PCR[89]
2
PADSEL2
3
0x502 CAN3RX / FlexCAN_3 00: PCR[36]
01: PCR[73]
10: PCR[89]
2
PADSEL3
4
0x503 CAN4RX / FlexCAN_4 00: PCR[35]
01: PCR[43]
10: PCR[95]
2