Memory Map for Major Havoc Alpha Processor D D D D D D D D Hex Address 7 6 5 4 3 2 1 0 Function -------------------------------------------------------------------------------- 0000-01FF | D D D D D D D D | R/W | Program RAM (1/2K) 0200-07FF | D D D D D D D D | R/W | Paged Program RAM (3K) 0800-09FF | D D D D D D D D | R/W | Program RAM (1/2K) | | | 1000 | D D D D D D D D | R | Gamma Commuication Read Port | | | 1200 | D | R | Right Coin Switch (Player 1=0) 1200 | D | R | Left Coin Switch (Player 1=0) 1200 | D | R | Aux. Coin Switch (Player 1=0) 1200 | D | R | Diagnostic Step 1200 | D | R | Self Test Switch (Player 1=1) 1200 | D | R | Cabinet Switch (Player 1=1) 1200 | D | R | Aux. Coin Switch (Player 1=1) 1200 | D | R | Diagnostic Step 1200 | D | R | Gammma Rcvd Flag 1200 | D | R | Gamma Xmtd Flag 1200 | D | R | 2.4 KHz 1200 | D | R | Vector Generator Halt Flag | | | 1400-141F | D D D D | W | ColorRAM | | | 1600 | D | W | Invert X 1600 | D | W | Invert Y 1600 | D | W | Player 1 1600 | D | W | Not Used 1600 | D | W | Gamma Proc. Reset 1600 | D | W | Beta Proc. Reset 1600 | D | W | Not Used 1600 | D | W | Roller Controller Light | | | 1640 | | W | Vector Generator Go 1680 | | W | Watchdog Clear 16C0 | | W | Vector Generator Reset | | | 1700 | | W | IRQ Acknowledge 1740 | D D | W | Program ROM Page Select 1780 | D | W | Program RAM Page Select 17C0 | D D D D D D D D | W | Gamma Communication Write Port | | | 1800-1FFF | D D D D D D D D | R/W | Shared Beta Communication RAM(not used) | | | 2000-3FFF | D D D D D D D D | R | Paged Program ROM (32K) 4000-4FFF | D D D D D D D D | R/W | Vector Generator RAM (4K) 5000-5FFF | D D D D D D D D | R | Vector Generator ROM (4K) 6000-7FFF | D D D D D D D D | R | Paged Vector Generator ROM (32K) 8000-FFFF | D D D D D D D D | R | Program ROM (32K) ------------------------------------------------------------------------------------ Gamma Processor D D D D D D D D Hex Address 7 6 5 4 3 2 1 0 Function -------------------------------------------------------------------------------- 0000-07FF | D D D D D D D D | R/W | Program RAM (2K) 2000-203F | D D D D D D D D | R/W | Quad-Pokey I/O | | | 2800 | D | R | Fire 1 Switch 2800 | D | R | Shield 1 Switch 2800 | D | R | Fire 2 Switch 2800 | D | R | Shield 2 Switch 2800 | D | R | Not Used 2800 | D | R | Speech Chip Ready 2800 | D | R | Alpha Rcvd Flag 2800 | D | R | Alpha Xmtd Flag | | | 3000 | D D D D D D D D | R | Alpha Comm. Read Port | | | 3800-3803 | D D D D D D D D | R | Roller Controller Input | | | 4000 | | W | IRQ Acknowledge 4800 | D | W | Left Coin Counter 4800 | D | W | Right Coin Counter | | | 5000 | D D D D D D D D | W | Alpha Comm. Write Port | | | 6000-61FF | D D D D D D D D | R/W | EEROM 8000-BFFF | D D D D D D D D | R | Program ROM (16K) -----------------------------------------------------------------------------