Specifications

Little Board™/486e Technical Manual
2–52
Jumpering the Byte-Wide Socket
You must jumper the byte-wide socket for the devices you install. Jumper array W2 configures S0
for a particular device type. Table 2–38 shows how to install jumpers for supported memory
devices.
Table 2–38. EPROM Jumpering for S0 (W2)
EPROM
Typical Devices
Pins Jumper Diagram
128K EPROM - 27C010
256K EPROM - 27C020
32
1
3
7
9
512K EPROM - 27C040
1M EPROM - 27C080
32
1
3
7
9
Byte-Wide Socket Signals
A jumper W2 for S0, configures the byte-wide sockets for specific memory devices. Table 2–39 lists
the signals that appear on the pins of W2.
Table 2–39. Byte-Wide Jumper Pin Signals (W2)
W14 Pin Signal
Name
Description
1 A18 Address A18 (static)
2 Pin 1 Connection to pin 1 of the byte-wide socket
3 A19 Address A19 (static)
4 Pin 31 Connection to pin 31 of the byte-wide socket
5 -SMEMW Write strobe
6 Pin 29 Connection to pin 29 of the byte-wide socket
7 A15 Address SA15 from the expansion bus
8 Pin 3 Connection to pin 3 of the byte-wide socket
9 A14 Address SA14 from the expansion bus