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Digi JACKRABBIT BL1800 User Manual

Page 71

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User’s Manual

67

As shown in Table A-3, pins PE4 and PE5 can instead be used as external INT0B and
INT1B interrupts. Pins PD6 and PD7 can instead be used to access Serial Port A on the
Rabbit 2000 microprocessor. Pins PB0 and PB1 can instead be used to access the clock on
Serial Port B and Serial Port A of the Rabbit 2000 microprocessor.

The four output-only pins are located on PB6–PB7, PCLK, and IOBEN. PB7 can also be
used with the slave port of the Rabbit 2000 microprocessor. The primary function of
PCLK is as a peripheral clock or a peripheral clock ÷ 2, but PCLK can instead be used as
a digital output. Similarly, IOBENB is an I/O buffer enable, but can instead be used as a
digital output. STAT and WDO also have limited uses as digital outputs.

PD0

Bitwise or parallel
programmable I/O,
can be driven or open-
drain output

PD1

Connected to control
DA0

PD2

Connected to control
DA0

PD3

PD4

ATXB output

Connected to control
DA1

PD5

ARXB input

Connected to RS-485 IC
data enable input

PD6

ATXA output

PD7

ARXA input

PE0

Bitwise or parallel
programmable I/O

I0 output or INT0A input HV0 output control

PE1

I1 output or INT1A input HV1 output control

PE2

I2 output

HV2 output control

PE3

I3 output

HV3 output control

PE4

I4 output or external
INT0B input

PE5

I5 output or external
INT1B input

PE6

I6 output

Connected to A/D
comparator output

PE7

I7 output or slave port
chip select /SCS

Connected to A/D
comparator output

PCLK

Peripheral clock

Output

IOBEN

I/O buffer enable

Output

WDO

Watchdog output

Single low pulse output

STAT

Status

Output

Connected to
programming port

Table A-3. Jackrabbit Pinout Configurations (continued)

Pin

Rabbit 2000

Factory Default

Alternate Use

Jackrabbit Use