Programming the FPGA

Physical Setup

• Use the red Xilinx USB cable box to connect the digital control board to the computer.
• The instructions for mapping the colored wires to the digital control board can be found in the "Data Acquisition Station Log + Readout Electronics Project" logbook on pg. 104 in the top left corner.
• 2->red; 4->green; 6->yellow; 8->purple; 10->white; 13->black; gray is unconnected

Xilinx Software

Editing the uParam program

• Open Xilinx ISE Project Manager
• In the top left window select FPGA_ctrl. This should have 2 boxes and a "+" with the top box green. This indicates a top level project.
• Select uParam within FPGA_ctrl.
• To change the maximum voltage for VBias, change the binary value for DAC_Qmax.
  • This is a 14-bit number which is found by following the formula commented out in the program. 3.3V has been used for the reference voltage.
• The maximum gainmode value can be changed similarly.
• Save the file.
• There should be orange question marks in the lower left window. Run "generate programming file". Yellow exclamation marks correspond to warnings but not errors.

Flashing the program

• Now that the program has been changed and saved, open the Xilinx IMPACT program.
• Open IMPACT and go to the folder c/work/Gluex/Tagger/Electronics/FPGA/TotalTest and check to see if fpga_ctrl.bgn and .bit are up to date
• Open fpga.ipf
• There should be 2 diagrams showing the devices on the programming device: TDinput (xcf01s_vo20 fpga.mcs), TDoutput (xc3s50a bypass)
  • EEPROM (on left, chip holds the programming in non-volatile memory and programs FPGA on startup)
  • FPGA on right, volatile and forgets its programming at every powerdown