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Port 3 (p3) – Texas Instruments MSC1210 User Manual

Page 316

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Bit Addressable SFRs (alphabetical)

F-6

Port 3 (P3)

SFR Name:

P3

SFR Address:

B0

H

Bit−Addressable: Yes

Bit−Definitions:

bit 7

bit 6

bit 5

bit 4

bit 3

bit 2

bit 1

bit 0

Name

RD

WR

T1

T0

INT1

INT0

TXD

RXD

Bit Address

B7H

B6H

B5H

B4H

B3H

B2H

B1H

B0H

RD—Read Strobe. 0 = external memory read strobe.

WR—Write Strobe. 0 = external memory write strobe.

T1—Timer/Counter 1 External Input. Optionally used to control timer/counter
1 via external source.

T0—Timer/Counter 0 External Input. Optionally used to control timer/counter
0 via external source.

INT1—External Interrupt 1. Used to trigger external interrupt 1.

INT0—External Interrupt 0. Used to trigger external interrupt 0.

TXD—Serial Transmit Data. 8052 serial transmit line (from 8052 to external
device).

RXD—Serial Transmit Data. 8052 serial receive line (to 8052 from external
device).

Note:

These bit names indicate the function of that I/O line on the P3 bus. A stan-
dard 8052 assembler will not recognize these bits by the given names; they
will only be recognized as P3.7, P3.6, etc.