Little Board™/486e Technical Manual
2–4
Jumper Configuration Options
Ampro installs optional jumpers in default positions so that the Little Board/486e CPU requires no
special jumpering for immediate operation. Jumper-pin arrays are designated W1, W2, and so
forth. Jumper pins have a 2mm pitch. A square solder pad identifies pin 1 of each jumper array.
Table 2–2 provides a summary of jumper use. In the Default column, two numbers separated by a
slash (for example, 1/2) means that pins 1 and 2 are sho rted w ith a 2 mm j umper bloc k.
Table 2–2. Configuration Jumper Summary

Jumper

Group Function Default

W1 Memory SWAP ON
W2 Byte-Wide S0 Configuration
(default is Flash EPROM) 1 /2, 4/5, 7/8, 6 /9
W3 Compact Flash Master/Slave Selector OFF (Slave)
W4 Watchdog Timer Output Selec t
(IOCHECK, Reset) OFF (No Selection)
W5 Serial 2 RS-232/RS-485 Select 1/2 (RS-232)
W6 RS-485 Termination Enable OFF (No Enable)
W7 Serial 3/4 IRQ Sharing 2/3 (Non-sharing)
W8 Serial 3 IRQ Selector 1/2 (IRQ 11)
W9 Serial 4 IRQ Selector 1/2 (IRQ 10)
W10 LCD Power Selector 1/3 and 2/4 (+5V)
W11/W12 Video Controller Enable ON/ON (Enable)
W13 Ethernet SEEP Enable OFF (Enable)
W14 Power Fail Monitor NMI Enable OFF (No Enable)
System I/O Map
Table 2–3 lists the I/O port assignments of the Little Board/486e CPU. The I/O port functions and
addresses are both hardware and software compatible for all standard PC applications.
The ROM BIOS typically provides all of the services needed to use the onboard and I/O port
connected devices. If you need to directly program the standard functions, refer to a programming
reference for the PC/AT.