3 digital i/o registers – Texas Instruments MSP430x4xx User Manual
Page 190
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Digital I/O Registers
9-7
Digital I/O
9.3
Digital I/O Registers
Seven registers are used to configure P1 and P2. Four registers are used to
configure ports P3 - P6. The digital I/O registers are listed in Table 9−1.
Table 9−1. Digital I/O Registers
Port
Register
Short Form
Address
Register Type
Initial State
P1
Input
P1IN
020h
Read only
−
Output
P1OUT
021h
Read/write
Unchanged
Direction
P1DIR
022h
Read/write
Reset with PUC
Interrupt Flag
P1IFG
023h
Read/write
Reset with PUC
Interrupt Edge Select
P1IES
024h
Read/write
Unchanged
Interrupt Enable
P1IE
025h
Read/write
Reset with PUC
Port Select
P1SEL
026h
Read/write
Reset with PUC
P2
Input
P2IN
028h
Read only
−
Output
P2OUT
029h
Read/write
Unchanged
Direction
P2DIR
02Ah
Read/write
Reset with PUC
Interrupt Flag
P2IFG
02Bh
Read/write
Reset with PUC
Interrupt Edge Select
P2IES
02Ch
Read/write
Unchanged
Interrupt Enable
P2IE
02Dh
Read/write
Reset with PUC
Port Select
P2SEL
02Eh
Read/write
Reset with PUC
P3
Input
P3IN
018h
Read only
−
Output
P3OUT
019h
Read/write
Unchanged
Direction
P3DIR
01Ah
Read/write
Reset with PUC
Port Select
P3SEL
01Bh
Read/write
Reset with PUC
P4
Input
P4IN
01Ch
Read only
−
Output
P4OUT
01Dh
Read/write
Unchanged
Direction
P4DIR
01Eh
Read/write
Reset with PUC
Port Select
P4SEL
01Fh
Read/write
Reset with PUC
P5
Input
P5IN
030h
Read only
−
Output
P5OUT
031h
Read/write
Unchanged
Direction
P5DIR
032h
Read/write
Reset with PUC
Port Select
P5SEL
033h
Read/write
Reset with PUC
P6
Input
P6IN
034h
Read only
−
Output
P6OUT
035h
Read/write
Unchanged
Direction
P6DIR
036h
Read/write
Reset with PUC
Port Select
P6SEL
037h
Read/write
Reset with PUC