VersaLogic VL-EBX-18, Hardware Reference Manual, Page: 52 / 63

Interfaces and Connectors
EBX-18 Hardware Reference manual
45
SPX™ Expansion Bus
Up to four serial peripheral expansion (SPX) devices can be attached to the EBX-18 at connector
J17 using a CBR-1401 or CBR-1402 cable. The SPX interface provides the standard SPI signals
(SCLK, MISO, and MOSI), four chip selects (SS0# - SS3#), and an interrupt input (SINT#).
Table 31: SPI Expansion Bus Connections
Pin Signal Function Pin Signal Function
1 V5_0 +5.0 V 2 SCLK Serial Clock
3 GND Ground 4 MISO Serial Data In
5 GND Ground 6 MOSI Serial Data Out
7 GND Ground 8 SS0# Chip Select 0
9 SS1# Chip Select 1 10 SS2# Chip Select 2
11 SS3# Chip Select 3 12 GND Ground
13 SINT# Interrupt Input 14 V5_0 +5.0 V
Figure 19. J17 SPX Connector Pin Configuration
V
ERSA
L
OGIC
SPX E
XPANSION
M
ODULES
VersaLogic offers several SPX modules that provide a variety of standard functions, such as
analog input, digital I/O, CANbus controller, and others. These are small boards (1.2” x 3.775”)
that can mount on the PC/104 and PC/104-
Plus stack, using standard PC/104 stand-offs, or up to
two feet away from the base board. For more information, contact VersaLogic at
info@VersaLogic.com .
PC/104 Expansion Bus
The Vortex86DX2 ISA bus interface is an 8/16-bit ISA device with zero-wait-state and is
available through the Vortex86DX2 SoC’s internal ISA-to-PCI bridge. The maximum ISA clock
frequency is 33 MHz. The AT clock is programmable. The SoC generates refresh signals to the
ISA interface during the DRAM refresh cycle. (This means the ISA Refresh signal would be
modified with the DRAM refresh rate change from ~15
μs to ~3.9 μs).