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Zilog EZ80L92 User Manual

Page 43

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eZ80L92 Development Kit

User Manual

UM012913-0407

Operational

Description

39

Jumper J18
The J18 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 22

.

Jumper J19
The J19 jumper connection selects the range of memory addresses for the
external chip select signal, CS_EX, to the application module. See

Table 23

.

Table 22. J18—RT_2*

Shunt
Status

Function

Affected Device

IN

The Termination Resistor for RS485_2 is IN.

RS485 interface.

OUT

The Termination Resistor for RS485_2 is OUT.

RS485 interface.

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

Table 23. J19—EX_SEL

Shunt
Status

Function

Affected Device

1–2

CS_EX is decoded in the CS0 memory space and is
located in the address range 400000h–7FFFFFh.

Application module
addressing.

3–4

CS_EX is decoded in the CS2 memory space and is
located in the address range A00000h–A7FFFFh.

Application module
addressing.

5–6

CS_EX is decoded in the CS2 memory space and is
located in the address range A80000h–AFFFFFh.

Application module
addressing.

7–8

CS_EX is decoded in the CS2 memory space and is
located in the address range B00000h–B7FFFFh.

Application module
addressing.