8XC152JAJBJCJD

Pin

Pin Description

DIP

48

2

24

18-21

27-30

Port 0

Port 0 is an 8-bit open drain bidirectional IO port As an output port each pin

25-28

34-37

can sink 8 LS TTL inputs Port 0 pins that have 1s written to them float and in that

state can be used as high-impedance inputs

Port 0 is also the multiplexed low-order address and data bus during accesses to

external program memory if EBEN is pulled low During accesses to external Data

Memory Port 0 always emits the low-order address byte and serves as the multiplexed

data bus In these applications it uses strong internal pullups when emitting 1s

Port 0 also outputs the code bytes during program verification External pullups are

required during program verification

1-8

4-11

Port 1

Port 1 is an 8-bit bidirectional IO port with internal pullups Port 1 pins that

have 1s written to them are pulled high by the internal pullups and in that state can be

used as inputs As inputs Port 1 pins that are externally being pulled low will source

Port 1 also serves the functions of various special features of the 8XC152 as listed

below

Pin

Name

Alternate Function

P10

GRXD

GSC data input pin

P11

GTXD

GSC data output pin

P12

DEN

GSC enable signal for an external driver

P13

TXC

GSC input pin for external transmit clock

P14

RXC

GSC input pin for external receive clock

P15

HLD

DMA hold inputoutput

P16

HLDA

DMA hold acknowledge inputoutput

29-36

41-48

Port 2

Port 2 is an 8-bit bidirectional IO port with internal pullups Port 2 pins that

have 1s written to them are pulled high by the internal pullups and in that state can be

used as inputs As inputs Port 2 pins that are externally being pulled low will source

Port 2 emits the high-order address byte during fetches from external Program

Memory if EBEN is pulled low During accesses to external Data Memory that use 16-

bit addresses (MOVX

DPTR and DMA operations) Port 2 emits the high-order

address byte In these applications it uses strong internal pullups when emitting 1s

During accesses to external Data Memory that use 8-bit addresses (MOVX

Ri)

Port 2 emits the contents of the P2 Special Function Register

Port 2 also receives the high-order address bits during program verification

10- 17

14-16

Port 3

Port 3 is an 8-bit bidirectional IO port with internal pullups Port 3 pins that

18 19

have 1s written to them are pulled high by the internal pullups and in that state can be

23-25

used as inputs As inputs Port 3 pins that are externally being pulled low will source

Port 3 also serves the functions of various special features of the MCS-51 Family as

listed below

Pin

Name

Alternate Function

P30

RXD

Serial input line

P31

TXD

Serial output line

P32

INT0

External Interrupt 0

P33

INT1

External Interrupt 1

P34

T0

Timer 0 external input

P35

T1

Timer 1 external input

P36

WR

External Data Memory Write strobe

P37

RD

External Data Memory Read strobe

5