DarFPGA Files

-------------------------------------------------------------------------------
-- Inferno by Dar (darfpga@aol.fr) (13 March 2022)
-- http://darfpga.blogspot.fr
-- https://sourceforge.net/projects/darfpga/files
-- github.com/darfpga
--
--  Terasic board MAX10 DE10 Lite
-------------------------------------------------------------------------------
-- gen_ram.vhd & io_ps2_keyboard
-------------------------------- 
-- Copyright 2005-2008 by Peter Wendrich (pwsoft@syntiac.com)
-- http://www.syntiac.com/fpga64.html
-------------------------------------------------------------------------------
-- cpu09l - Version : 0128
-- Synthesizable 6809 instruction compatible VHDL CPU core
-- Copyright (C) 2003 - 2010 John Kent
-------------------------------------------------------------------------------
-- cpu68 - Version 9th Jan 2004 0.8
-- 6800/01 compatible CPU core 
-- GNU public license - December 2002 : John E. Kent
-------------------------------------------------------------------------------
-- Educational use only
-- Do not redistribute synthetized file with roms
-- Do not redistribute roms whatever the form
-- Use at your own risk
-------------------------------------------------------------------------------
--  Video 15KHz is OK, 
--
--  This is not VGA, you have to use a TV set with SCART plug
--
--    SCART(TV) pin  - signal -  VGA(DE10) pin
--               15  -  red   -  1          
--               11  - green  -  2
--                7  -  blue  -  3  
--           5,9,13  -  gnd   -  5,6,7
--   (comp. sync)20  - csync  -  13 (HS)   
--  (fast commut)16  - commut -  14 (VS)
--            17,18  -  gnd   -  8,10 
--
-------------------------------------------------------------------------------
-- Version 0.0 -- 13/03/2022 -- 
--	initial version 
-------------------------------------------------------------------------------
--
-- Main features :
--  PS2 keyboard input @gpio pins 35/34 (beware voltage translation/protection)
--  Audio pwm output   @gpio pins 1/3 (beware voltage translation/protection)
--
-- Uses 1 pll for 12MHz and 120MHz generation from 50MHz
--
-- Board key :
--   0 : reset game
--
-- Keyboard players inputs :
--
--   F3 : Add coin
--   F2 : Start 2 players
--   F1 : Start 1 player
--   SPACE       : Fire  
--   RIGHT arrow : run/aim -- must use separate controls
--   LEFT  arrow : run/aim -- must use separate controls
--   UP    arrow : run/aim -- must use separate controls 
--   DOWN  arrow : run/aim -- must use separate controls
--   CTRL        : NU
--   W(Z)        : NU
--
-- Keyboard Service inputs French(english) :
--
--   A(Q) : advance
--   U(U) : auto/up (!manual/down)
--   H(H) : high score reset
--
-- To enter service mode press 'advance' key while in game over screen
-- Enter service mode to tune game parameters (difficulty ...)
-- Tuning are lost at power OFF, for permanent tuning edit/set parameters
--   within inferno_cmos_ram.vhd and recompile.
--
-------------------------------------------------------------------------------
-- Use make_inferno_proms.bat to build vhd file and bin from binaries
-- Load sdram with external rom bank -> use sdram_loader_de10_lite.sof + key(0)
-------------------------------------------------------------------------------
-- Program sdram content with this  inferno rom bank loader before 
-- programming inferno game core :
--
-- 1) program DE10_lite with inferno sdram loader
-- 2) press key(0) at least once (digit blinks during programming)
-- 3) program DE10_lite with inferno core without switching DE10_lite OFF
-------------------------------------------------------------------------------
-- Used ROMs by make_inferno_proms.bat

> inferno_prog2
   ic9.inf  CRC(1a013185)
   ic10.inf CRC(dbf64a36)

> inferno_bank_a
  None  

> inferno_bank_b
   ic25.inf CRC(103a5951)
   ic23.inf CRC(c04749a0)
   ic21.inf CRC(c405f853)
   ic19.inf CRC(ade7645a)   

> inferno_bank_c
   ic18.inf CRC(95bcf7b1)
   ic16.inf CRC(8bc4f935)
   ic14.inf CRC(a70508a7)
   ic12.inf CRC(7ffb87f9)

> inferno_bank_d
   ic17.inf CRC(b4684139)
   ic15.inf CRC(128a6ad6)
   ic13.inf CRC(83a9e4d6)
   ic11.inf CRC(c2e9c909)

> inferno_sound
   ic8.inf  CRC(4e3123b8)

> inferno_graph1
   ic57.inf CRC(65a4ef79)

> inferno_graph2
   ic58.inf CRC(4bb1c2a0)

> inferno_graph3
   ic41.inf CRC(f3f7238f)

-------------------------------------------------------------------------------
-- Misc. info
-------------------------------------------------------------------------------
-- Main bus access
--  > Main address bus and data bus by CPU 6809
--  > Main address bus and data bus by DMA (blitter) while CPU is halted.
--
-- CPU and DMA can read/write anywhere from/to entire 64K address space
-- including video ram, color palette, tile map, cmos_ram, peripherals, roms,
-- switched rom banks, ...

--
-- Page register control allows to select misc. banked access (rom, ram). 
-------------------------------------------------------------------------------
-- Video ram : 3 banks of 16Kx8 (dram with ras/cas)
--  > interleaved bank access by CPU, 8bits read/write
--  > interleaved bank access by DMA, 8bits read, 2x4bits independent write
--  > simultaneous (3 banks) access by video scanner, 24bits at once
-- 
-- In original hardware, every 1us there is 1 access to video ram for CPU/DMA
-- and 1 access for video scanner. Thus DMA read/write cycle required 2us when
-- reading source is video ram. DMA read/write cycle required only 1us when
-- reading source is not video ram.
--
-- Higher part of video ram is not displayed on screen and is used as working
-- ram by CPU including stack (SP).
-------------------------------------------------------------------------------
-- Foreground (bitmap - video ram)
--  > 24 bits / 1us => 6 horizontal pixels of 4bits (16 colors)
--  > 6 bits register (64 color banks)
-------------------------------------------------------------------------------
-- Background (tile map : tile is 24x16 pixels)
--
--  > 16 horizontal tiles of 4x6 pixels, 16 vertical tiles of 16 pixels.
--  > map ram 2048x8
--      in  : 7 bits horizontal (4 bits + scroll) + 4 bits vertical
--      out : 128 possible tiles + flip control
--
--  > Graphics 3x8Kx8 roms
--      in  : 2 bits horizontal + 4 bits vertical + 7 bits tile code 
--      out : 24 bits = 6 pixels x 4 bits
--
--  > 24 bits / 1us => 6 horizontal pixels of 4bits (16 colors)
--  > 3 bits register + 3 bits from vertical video scanner (64 color banks)
-------------------------------------------------------------------------------
-- Palette 1024 colors x 16 bits
--  > in  10 bits from foreground or background data
--  > out 4 bits red, 4 bits green, 4 bits blue, 4 bits intensity 
-------------------------------------------------------------------------------