Little Board/P5x Technical Manual
2–55
Using Standard PC and AT Bus Cards
Ampro offers several options that allow you to add convention al 8-bit and 16- bit ISA exp ansion
cards to the Little Board/P5x system. Contact Ampro for further information about optio nal bus
expansion products.
Expansion Bus Connector Pinouts
Table 2– 50 through Table 2– 54 show the pinout and signal functions on the PC/104-Plus-
compatible expansion bus connectors. These include P1, P2, and J21.
The Little Board/P5x does not generate ±12VDC, 3.3V, or -5VDC for the expansion bus. If devices
on the bus require these voltages, -12V and -5V can be supplied to the bus connector from the
Utility 1 connector (J16). +12V can be supplied through J10-4. If a PCI peripheral board requires
3.3V, you can attach this voltage to J10-5.
You do not need to add a +12V supply to program the on-board Flash device that stores the ROM
BIOS, video BIOS, SCSI BIOS, and optional Ethernet boot PROM code. An on-board supply
provides the programming voltage. This supply, however, does not provide power to the expansion
bus. Most Ampro expansion products provide on-board DC-to-DC converters to convert the +5V
supply to other voltages they require.
The expansion bus pin numbers for P1 and P2, shown in the following tables, correspond to the
scheme normally used on ISA expansion bus card sockets. Rather than numerical designations (1, 2,
3) they have alpha-numeric designations (A1, A2…, B1, B2…, etc.). Similarly, the rows of J21 are
designated A, B, C, and D.