Digital Video Display Adapter for the TRS-80 Model 3 and Model 4

A through-hole remix of Matt Boytim's TRS-80 FPGA Digital Video display adapter. Created with EasyEDA.

This remix removes the unused VGA connections, adds some useful powering options, adds additional silkscreen descriptions, and uses all through-hole parts for ease of assembly by the hobbyist.

Minimum Required parts:

• QTY 1 Tang Nano 9K FPGA board with headers and programmed with bitstream from above for the appropriate Model, either 3 or 4.
• QTY 2 24 Pin Female to Male 2.54mm headers for attaching Tang Nano 9K to the PCB
• QTY 2 2 Position Male to Male 2.54mm Pin Headers for use with J3 and J5
• QTY 1 3 Position Male to Male 2.54mm Pin Headers for use with H1
• QTY 3 2.54mm Jumper Shunts like TE Connectivity 2-881545-2
• QTY 1 Texas Instruments SN74LV125AN Quad Bus Buff Gate With 3-State Outputs, or equivalent for U1.
• QTY 1 L7805 Linear Voltage Regulator, or equivalent DC/DC voltage converter regulator for U3
• QTY 1 10uF Capacitor, Radial Leads for C1
• QTY 2 1uF Capacitor, Radial Leads for C3 and C4
• QTY 1 0.1uF Capacitor, Radial Leads for C2
• QTY 2 Axial 1K Ohm 1/4 Watt Resistors for R6 and R7

Mouser Cart with all parts available here: https://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=4506e6a91b

Additional Optional Parts:

• QTY 2 6 Position Male to Male 2.54mm Pin Headers for use with Video Input from Motherboard for direct connection without the CRT Harness, with pass-through connector option to continue using the harness and output adapter at the same time.
• QTY 1 16 Pin 2x8 Male to Male 2.54mm Pin Headers for use with J4 Option Jumpers for color settings
• QTY 1 Molex 22-05-1042 Male Right Angle 4 Pin Header for power via system power supply, or for use as pass-thru power. Do not operate power-hungry devices off of 5V output of this connector!

Special thanks to Matt Boytim and all of the TRS-80 community for creating awesome enhancements like these.