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CP3BT26
In the descriptions of the ports and port registers, the lower-
case letter “x” represents the port designation, either B, C,
E, F, G, H, or J. For example, “PxDIR register” means any
one of the port direction registers: PBDIR, PCDIR, PEDIR,
PFDIR, PGDIR, PHDIR, or PJDIR.
Table 29 Port Registers
Name Address Description
PBALT FF FB00h
Port B Alternate
Function Register
PBDIR FF FB02h Port B Direction Register
PBDIN FF FB04h Port B Data Input Register
PBDOUT FF FB06h Port B Data Output Register
PBWPU FF FB08h
Port B Weak Pull-Up
Register
PBHDRV FF FB0Ah
Port B High Drive
Strength Register
PBALTS FF FB0Ch
Port B Alternate Function
Select Register
PCALT FF FB10h
Port C Alternate
Function Register
PCDIR FF FB12h Port C Direction Register
PCDIN FF FB14h Port C Data Input Register
PCDOUT FF FB16h Port C Data Output Register
PCWPU FF FB18h
Port C Weak Pull-Up
Register
PCHDRV FF FB1Ah
Port C High Drive
Strength Register
PCALTS FF FB1Ch
Port C Alternate Function
Select Register
PEALT FF FCC0h
Port E Alternate
Function Register
PEDIR FF FCC2h Port E Direction Register
PEDIN FF FCC4h Port E Data Input Register
PEDOUT FF FCC6h Port E Data Output Register
PEWPU FF FCC8h
Port E Weak Pull-Up
Register
PEHDRV FF FCCAh
Port E High Drive
Strength Register
PEALTS FF FCCCh
Port E Alternate Function
Select Register
PFALT FF FCE0h
Port F Alternate
Function Register
PFDIR FF FCE2h Port F Direction Register
PFDIN FF FCE4h Port F Data Input Register
PFDOUT FF FCE6h Port F Data Output Register
PFWPU FF FCE8h
Port F Weak Pull-Up
Register
PFHDRV FF FCEAh
Port F High Drive
Strength Register
PFALTS FF FCECh
Port F Alternate Function
Select Register
PGALT FF F300h
Port G Alternate
Function Register
PGDIR FF F302h Port G Direction Register
PGDIN FF F304h Port G Data Input Register
PGDOUT FF F306h Port G Data Output Register
PGWPU FF F308h
Port G Weak Pull-Up
Register
PGHDRV FF F30Ah
Port G High Drive
Strength Register
PGALTS FF F30Ch
Port G Alternate Function
Select Register
PHALT FF F320h
Port H Alternate
Function Register
PHDIR FF F322h Port H Direction Register
PHDIN FF F324h Port H Data Input Register
PHDOUT FF F326h Port H Data Output Register
PHWPU FF F328h
Port H Weak Pull-Up
Register
PHHDRV FF F32Ah
Port H High Drive
Strength Register
PHALTS FF F32Ch
Port H Alternate Function
Select Register
PJALT FF F340h
Port J Alternate
Function Register
PJDIR FF F342h Port J Direction Register
PJDIN FF F344h Port J Data Input Register
PJDOUT FF F346h Port J Data Output Register
PJWPU FF F348h
Port J Weak Pull-Up
Register
PJHDRV FF F34Ah
Port J High Drive
Strength Register
PJALTS FF F34Ch
Port J Alternate Function
Select Register
Table 29 Port Registers
Name Address Description