XESS XStend XS40, Manual

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them access to all the resources of the XStend Board. To use an XS40 Board with the
XStend Board, insert it into the right-most columns of the socket strips. When using an
XS95 Board, you should insert it into the left-most columns of the sockets. There are
markings on the XStend Board to indicate the appropriate column for each type of XS
Board.
If the XS Board is connected to a power supply through jack J9, then its power regulation
circuitry will supply VCC and GND to the XStend Board through the mounting sockets.
XS40 Boards with 3.3V FPGAs will supply both 3.3V and 5V to the XStend Board, while
XS40 Boards with 5V FPGAs and XS95 Boards will supply only 5V.
Warning: Version 1.0 of the XS40 Board with a 3.3V XC4000XL FPGA will not work
with the XStend Board because it supplies 3.3V but no 5V! You must replace the
XC4000XL FPGA with an XC4000E FPGA and remove the J8 jumper on the XS40
board to switch the board to 5V operation. Ignore this warning if you have Version
1.1 or higher.
External voltage supplies can also be used with the XStend Board. A 5V power supply
can be connected to header J12 and a 3.3V supply can be attached to header J14 as
shown in Figure 2. These supplies will power the attached XS Board as well as the
XStend electronics.