National CP3BT26 User Manual

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68

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. 

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