Expansion Interfaces
EBX-38 Hardware Reference Manual
48
PC/104-
Plus
Expansion Bus
The EBX-38 provides a legacy stack-up PCI connector at locations J11(for PCI) and J10A and
J10B (for ISA) on the top side of the board for PC/104-
Plus
(PCI +ISA) as well as PCI-104 (PCI
only) and PC/104 (ISA only) expansion modules.
Figure 2 on page 2 shows the locations of these connectors.
The following table lists the maximum PC/104-
Plus
slot current rating on the EBX-38. This is
the aggregate power available to both the PCI and ISA connectors. ISA does not use +3.3V
power, so all of the +3.3 V power is available for the PCI connector.
Table 24: PC/104-
Plus
Connectors Maximum Current
Voltage
Maximum Current
+5 V
4.0 A
+3.3 V
3.0 A
+12 V
1.0 A
–12 V
0.5 A
ISA
B
US
(
ON
PC/104-
P
LUS
AND
PC/104
E
XPANSION
M
ODULES
)
Refer to the ISA sections of the
for a complete description of this
interface.
The EBX-38 implements the ISA bus on PC/104-
Plus
and PC/104 expansion modules using an
LPC-to-ISA bridge implemented in the FPGA. This LPC-to-ISA bridge supports all features
except the following:
The ISA bus must not be mastered by an external module. The EBX-38 is always the bus
master. The MASTER signal on pin D17 of J10 is not connected.
The REFRESH output signal on B19 of J10 is not supported; it is pulled up to a high logic
level.
DMA is not supported. The seven DACKx outputs on pins B15, B17, B26, D8, D10, D12,
and D14 on J10 are pulled up to a high logic level. The seven DRQx inputs on pins B6, B16,
B18, D9, D11, D13, and D15 on J10 are not connected. The Terminal Count (TC) output on
pin B27 of J10 is pulled low.
–5.0V power is not provided on J10 pin B5. This pin is not connected.
Most PC/104-
Plus
(PCI +ISA) or PC/104 (ISA only) expansion modules will work, but be sure to
check the requirements of your PC/104 card against the list above.
ISA
I/O
S
UPPORT
Both 8-bit and 16-bit I/O cycles are supported, but for 16-bit cycles the PC/104 (ISA) module
must be 16-bit capable and must assert IOCS16#.
