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68
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