Embedded Solutions
Page 6 of 46
Product Description
The PMC-XM-DIFF features a Xilinx Spartan3-1500 676 pin FPGA to implement the
PCI interface and two independent I/O channels each with a separate input and output
scatter-gather DMA engine to move data to/from host memory over the local 32-bit 33
MHz PCI bus. A Xilinx Virtex4 668 pin FPGA interfaces between the Spartan3 and the
IO. The IO can be configured with RS-485, LVDS or both.
Each IO has separate direction, and termination controls to allow any combination of
inputs and outputs. Impedance controlled and length matched within the mil [.001”] to
allow for any user requirement.
Other features include on-board PLL, optional RAM (1Mx36-bit QDDRII RAM),
temperature sensor, DIP Switch, Built in DMA, and user LED’s.
PCI IF
Data Flow
Control
FPGA
1M x 36 RAM
DMA
RX
TX
4Kx32
FIFO
4Kx32
FIFO
RX
TX
4Kx32
FIFO
4Kx32
FIFO
User Virtex
PLL
34 LVDS / RS-485 IO
Programmable Terminations
LEDs(4)
DIPSWITCH
TEMP
SENSOR
FIGURE 1
PMC-XM-DIFF BLOCK DIAGRAM
The engineering kit comes with a basic design for the Virtex consisting of the VHDL
package used to generate the ATP implementation. The design includes decoding,
DMA , two channels, IO loop-back and more. The package can include the Windows®
driver and reference code. The reference software is provided as source and can be