DECA port for Zaxxon by Somhic (03/07/21) adapted from DE10_lite port by Dar (https://sourceforge.net/projects/darfpga/files/Software%20VHDL/zaxxon/)

Read history of Zaxxon Arcade.

Features:

• It does not require SDRAM.
• HDMI video output (special resolution will not work on all LCD monitors)
• VGA 444 video output is available through GPIO (see pinout below).
  • VGA (30 kHz) & RGB (15 kHz) modes available. Toggle VGA / RGB with F8 key
  • Tested with PS2 & R2R VGA adapter (333) https://www.waveshare.com/vga-ps2-board.htm
• NO AUDIO AVAILABLE IN THIS CORE YET
• Joystick available through GPIO (see pinout below). Joystick power pin must be 2.5 V
  • DANGER: Connecting power pin above 2.6 V may damage the FPGA
  • This core is prepared for Megadrive 6 button gamepads as it outputs a permanent high level on pin 7 of DB9

Additional hardware required:

• PS/2 Keyboard connected to GPIO (see pinout below)

Versions:

• v1 initial revision
• v2 added video_vs & video_hs in zaxxon.vhd
• v3 HDMI working. Added video_clk output in zaxxon.vhd
• v3.1. VGA & RGB versions working.

see changelog in top level file /deca/zaxxon_deca.vhd

Compiling:

• Load project from /deca/zaxxon_deca.qpf

• sof/svf files already included in /deca/output_files/

Pinout connections:

Others:

• Button KEY0 is a reset button

• Working fine

• HDMI video outputs special resolution so will not work on all monitors.

• No audio possible without adding SDRAM due to the way the original ROM was made.

F1 : Add coin F2 : Start 1 player F3 : Start 2 players

SPACE : fire RIGHT arrow : move right LEFT arrow : move left UP arrow : move up DOWN arrow : move down

F4 : flip screen (additional feature) F5 : Service mode ?! (not tested) F7 : uprigth/cocktail mode (required reset) F8 : toggles VGA / RGB video mode

Other details : see original README.txt / zaxxon.vhd

• You would need the original MAME ROM files
• Use tools included to convert ROM files to VHDL (read original README.txt)
• put the VHDL ROM files (.vhd) into the rtl_dar/proms directory
• build zaxxon_deca
• program zaxxon_deca.sof

You can build the project with ROM image embedded in the sof file. DO NOT REDISTRIBUTE THESE FILES