PXR40RM Datasheet, PDF (268/1434 Pages) Freescale Semiconductor, Inc – PXR40 Microcontroller

System Integration Unit (SIU)
7.3.1.35 GPIO Pin Data Input Registers (SIU_GPDI0_3 - SIU_GPDI508_511) -
Standard
Previous devices are limited to supporting a maximum of 256 general purpose input registers, and thus a
maximum GPIO input assignment of GPIO[0:255]. The reason is that only 256 bytes of SIU address space
is allocated for the GPIO Pin Data Input registers, and adjacent memory locations are unavailable.
To accommodate the extended number of the GPIO pads, this device has a new memory map definition of
512 bytes for allocating up to 512 GPIO Pin Data Input registers. For compatibility, the first used 256
GPIO Pin Data Input registers are mapped to both the old and new locations. The memory map is shown
in Table 7-66.
Table 7-66. GPIO Pin Data Input Registers Memory Map
Address Offset
from SIU_BASE
Number
0x0E00 - 0x0E4A Reserved
0x0E4B - 0x0E6E GPIO Pin Data Input Registers 75 - 110
0x0E6F - 0x0E70 Reserved
0x0E71 - 0x0ECC GPIO Pin Data Input Registers 113- 204
0x0ECD - 0x0ECF Reserved
0x0ED0 - 0x0ED1 GPIO Pin Data Input Registers 208- 209
Reserved
0x0ED3
GPIO Pin Data Input Registers 211
Reserved
0x0ED5
GPIO Pin Data Input Registers 213
Reserved
0x0EE7 - 0x0EFD GPIO Pin Data Input Registers 231 - 253
Reserved
0x0F00 - 0x0F33
0x0FB0 - 0x0FB5
0x0FB8 - 0x0FD8
GPIO Pin Data Input Registers 256 - 307
Reserved
GPIO Pin Data Input Registers 432 - 437
Reserved
GPIO Pin Data Input Registers 440 - 472
Reserved
The GPDIx_x registers are read-only registers that allow reading of the input state of an external GPIO pin.
Each byte of a register represents the input state of a single external GPIO pin. The first 256 GPDIx_x
registers corresponds to the same GPDI inputs described in Section 7.3.1.15, GPIO Pin Data Input
Registers 0–255 (SIU_GPDIn).
SIU_BASE+0x0E00
0
1
2
3
4
5
6
7
R
0
0
0
0
0
0
0 PDI0
W
RESET: 0
0
0
0
0
0
0
U
Figure 7-46. GPIO Pin Data In Register 0 (SIU_GPDI0)
7-86
PXR40 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor