;==============================================================================
;
; The following is what I know (I hope) about the ECU hardware and PAL mapping.
;
;
; Memory Map ............
;
;
;               +---------------------- A15     PAL
;               |+--------------------- A14     PAL  ROM
;               ||+-------------------- A13     PAL  ROM
;               |||+------------------- A12          ROM  Timer(CS1)
;               ||||+------------------ A11          ROM
;               |||||+----------------- A10          ROM  Timer(RS2)
;               ||||||+----------------  A9          ROM  Timer(RS1)
;               |||||||+---------------  A8          ROM  Timer(RS0)
;               |||||||| +-------------  A7
;               |||||||| |      +------  A0     A0-A7 PAL only
;               |||||||| |      |
;       0000    00000000 00000000       Base of System RAM  (512 bytes total)
;       00FF    00000000 11111111       Top of Direct addressed RAM
;       01FF    00000001 11111111       Top of System RAM (Extended Addressing)
;
;       1000    00010000 00000000       Base of 64-byte register block
;       103F    00010000 00111111       Top of register block
;
;       3000    00110000 00000000       Control Register #1 and #3
;       3100    00110001 00000000       Control Register #2
;       3200    00110010 00000000       MSB Buffer Register #1
;       3300    00110011 00000000       Timer #1 Latches
;       3400    00110100 00000000       MSB Buffer Register #2
;       3500    00110101 00000000       Timer #2 Latches
;       3600    00110110 00000000       MSB Buffer Register #3
;       3700    00110111 00000000       Timer #3 Latches
;
;       4000    01000000 00000000       PAL Output Latch
;       6000    01100000 00000000       PAL Input Latch
;
;       8000    10000000 00000000       First block of code
;       97DD    10010111 11011101       End of first block of code
;
;       B600    10110110 00000000       Base of EEPROM  (512 bytes)
;       B7FF    10110111 11111111       Top of EEPROM
;
;       D000    11010000 00000000       Start of second block of code
;       DDF6    11011101 11110110       End of second block
;
;       F000    11110000 00000000       ; Look up tables and constants
;       FFB6    11111111 10111111       ;......
;
;       FFC0    11111111 11000000       ; start of interrupt tables
;       FFFF    11111111 11111111       ; Top of 64k address space
;
; ----------------------------------------