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Zilog EZ80L92 User Manual

Page 42

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eZ80L92 Development Kit
User Manual

Operational Description

UM012913-0407

38

Jumper J16
The J16 jumper connection controls the selection of the RS485 circuit.
However, UART1 MODEM interface and the socket modem interface are
disabled if the RS485 circuit is enabled. When the shunt is placed, the
RS485 circuit is enabled. See

Table 20

.

Jumper J17
The J17 jumper connection controls the selection of the RS485 termina-
tion resistor circuit. When the shunt is placed, the RS485 termination
resistor circuit is enabled. See

Table 21

.

Table 20. J16—RS485_2_EN

Shunt
Status

Function

Affected Device

IN

The RS485 circuit is enabled on UART1. The
UART1 MODEM interface and the Socket
Modem interface are disabled.

UART1 MODEM interface,
Socket Modem Interface,
and RS485 interface.

OUT

The RS485 circuit is disabled on UART1.

UART1 MODEM interface,
Socket Modem Interface,
and RS485 interface.

Table 21. J17—RT_1*

Shunt
Status

Function

Affected Device

IN

The Termination Resistor for RS485_1 is IN.

RS485 interface.

OUT

The Termination Resistor for RS485_1 is OUT.

RS485 interface.

Note: *Before enabling the termination resistor, ensure that the device is located at the end of the
interface line.