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System Integration Unit (SIU)
MPC5566 Microcontroller Reference Manual, Rev. 2
Freescale Semiconductor
6-23
The following table describes the fields in the pad configuration control registers:
Table 6-19. SIU_PCR Field Descriptions
Field
Description
0–2
Reserved
3–5
PA
[0:2]
Pin assignment. Selects the function of a multiplexed pad. A separate port enable output signal from the
SIU is asserted for each value of this register. The size of the field can be from 1 to 3 bits, depending on
the amount of multiplexing on the pad.
6
OBE
Output buffer enable. Enables the pad as an output and drives the output buffer enable signal.
0 Disable output buffer for the pad.
1 Enable output buffer for the pad is enabled.
7
IBE
Input buffer enable. Enables the pad as an input and drives the input buffer enable signal.
0 Disable input buffer for the pad.
1 Enable input buffer for the pad is enabled.
8–9
DSC
[0:1]
Drive strength control. Controls the pad drive strength. Drive strength control pertains to pins with the fast
I/O pad type.
00 10 pF drive strength
01 20 pF drive strength
10 30 pF drive strength
11 50 pF drive strength
10
ODE
Open drain output enable. Controls output driver configuration for the pads. Either open drain or push/pull
driver configurations can be selected. This feature applies to output pins only.
0 Disable open drain for the pad (push/pull driver enabled).
1 Enable open drain for the pad.
PA Bit Field
Pin Function
1
1
For all SIU_PCRs that do not comply with these rules, the PA definition is
given explicitly with the SIU_PCR definition.
1-bit
2
(2 Functions)
2
For future software compatibility, it is recommended that all PA fields be
treated as 3-bit fields, with the unused bits written as 0.
2-bit
(4 Functions)
3-bit
(5 Functions)
0
0
0
0
0
0
0
0
0
GPIO
0
0
1
0
0
1
0
0
1
Primary function
0
1
0
0
1
0
Alternate function
0
1
1
0
1
1
Main primary function
3
3
The main primary function is used when the primary function is not available
on the package or is used for a different purpose.
The shaded columns indicate
invalid bits in 1- and 2-bit PA
fields; the shaded rows indicate
invalid values for 3-bit PA fields.
1
0
0
Alternate function 2
1
0
1
Invalid value
1
1
0
Invalid value
1
1
1
Invalid value
Summary of Contents for MPC5566
Page 81: ...Introduction MPC5566 Microcontroller Reference Manual Rev 2 1 24 Freescale Semiconductor...
Page 135: ...Signal Description MPC5566 Microcontroller Reference Manual Rev 2 2 54 Freescale Semiconductor...
Page 189: ...Reset MPC5566 Microcontroller Reference Manual Rev 2 4 20 Freescale Semiconductor...
Page 603: ...Flash Memory MPC5566 Microcontroller Reference Manual Rev 2 13 38 Freescale Semiconductor...
Page 609: ...SRAM MPC5566 Microcontroller Reference Manual Rev 2 14 6 Freescale Semiconductor...
Page 1073: ...MPC5566 Microcontroller Reference Manual Rev 2 22 36 Freescale Semiconductor...
Page 1185: ...Nexus MPC5566 Microcontroller Reference Manual Rev 2 25 92 Freescale Semiconductor...