Features
- 50 pin connector
- 12 Value LEDs (DB0-11) - octal format
- Display options: Program Counter (PC), Memory Address, Memory Data, Accumulator
- 12 Load Value Slide Switches (SL0-11) - octal format
- Enter values: PC, Memory Address, Memory Data, Accumulator
- LNK - Link value slide switch
- DISP - Display 12 Value LEDs select pushbutton
- Cycles between LEDs displaying PC, Memory Address, Memory Data, Accumulator
- Pushbutton Switches
- STEP pushbutton - Increment PC
- LDPC pushbutton - Load PC from Value Slide Switches
- DEP pushbutton - Store value from Value Slide Switches to memory
- LDA pushbutton - Store value from Value Slide Switches to Accumulator
- RES - Reset pushbutton - Resets CPU
- PB1 - spare pushbutton
- 4 DISP LEDs - Cycle between 12 LEDs source with DISP pushbutton
- PC - 12 LEDs display Program Counter value
- MADR - 12 LEDs display Memory Address value
- MD - 12 LEDs display Memory Data value
- AC - 12 LEDs display Accumulator value
- LINK LED - Displays Link value
- RUN LED - Running program
- RUN/HALT slide switch
- PWR - Power LED
- 95x95mm form factor
- (4) 6-32 mounting holes
PDP-8 FPGA Design
J1 Connector
- Extra power and ground pins (not on RETRO-EP4CE15 Card)
- Pins 3,4 = GND
- Pins 5-8 = VCC
- Pin 9 = N/C
Real PDP-8/F Front Panel
Pin List
# Clock, reset button
set_location_assignment PIN_T2 -to clk
set_location_assignment PIN_K22 -to btnCpuReset
set_instance_assignment -name WEAK_PULL_UP_RESISTOR ON -to btnCpuReset
# Run Switch/LED
set_location_assignment PIN_AA14 -to runSwitch
set_instance_assignment -name WEAK_PULL_UP_RESISTOR ON -to runSwitch
set_location_assignment PIN_E4 -to runLED
# Serial
set_location_assignment PIN_B13 -to RsRx
set_instance_assignment -name WEAK_PULL_UP_RESISTOR ON -to RsRx
set_location_assignment PIN_B10 -to RsTx
# PS/2
set_location_assignment PIN_R1 -to io_ps2Clk
set_instance_assignment -name WEAK_PULL_UP_RESISTOR ON -to io_ps2Clk
set_location_assignment PIN_R2 -to io_ps2Data
set_instance_assignment -name WEAK_PULL_UP_RESISTOR ON -to io_ps2Data
# VGA
set_location_assignment PIN_A17 -to o_vid_blu[1]
set_location_assignment PIN_B17 -to o_vid_blu[0]
set_location_assignment PIN_A16 -to o_vid_grn[1]
set_location_assignment PIN_B16 -to o_vid_grn[0]
set_location_assignment PIN_A15 -to o_vid_red[1]
set_location_assignment PIN_B15 -to o_vid_red[0]
set_location_assignment PIN_B18 -to o_vid_hSync
set_location_assignment PIN_A18 -to o_vid_vSync
# Front Panel
set_location_assignment PIN_AB15 -to btnc
set_location_assignment PIN_V21 -to btnd
set_location_assignment PIN_AB20 -to btnl
set_location_assignment PIN_P22 -to btnr
set_location_assignment PIN_AB17 -to btnu
set_location_assignment PIN_AA15 -to selLEDs[3]
set_location_assignment PIN_AA17 -to selLEDs[2]
set_location_assignment PIN_Y22 -to selLEDs[1]
set_location_assignment PIN_R21 -to selLEDs[0]
set_location_assignment PIN_AB14 -to sw[11]
set_location_assignment PIN_AB16 -to sw[10]
set_location_assignment PIN_AB18 -to sw[9]
set_location_assignment PIN_AB19 -to sw[8]
set_location_assignment PIN_AA20 -to sw[7]
set_location_assignment PIN_W21 -to sw[6]
set_location_assignment PIN_V22 -to sw[5]
set_location_assignment PIN_U22 -to sw[4]
set_location_assignment PIN_R22 -to sw[3]
set_location_assignment PIN_N22 -to sw[2]
set_location_assignment PIN_M22 -to sw[1]
set_location_assignment PIN_L22 -to sw[0]
set_location_assignment PIN_H21 -to sw[12]
PDP-8 Front Panel Assembly Sheet
PDP-8 Front Panel Assembly Sheet