Dual Roms

Honda Rom Maps are 256 kilobits (32kbytes) Use a 2xC512 (512kbit/64kbyte) EPROM Make one rom image with two full Rom Maps

• one beginning at offset 00h
• one beginning at offset 8000h

Take the High Bit Address A15 located at pin(1) use a switching device connect it to toggle between GND(14) and VCC(28). Be sure that pin1 is NOT connected to the socket, because there is constant 5V on the socket pin 1 and you'll short your ECU with the switch.

;With switch off (pin grounded) you get addresses in the form: 0xxx xxxx xxxx xxxx starting at offset 00h

;With switch on (pin +5v) you get addresses in the form: 1xxx xxxx xxxx xxxx starting at offset 8000h

It might be neccesary to disable checksums in both roms. If you are going to switch on the fly (i.e. nitrous), try to keep the roms identical except for the maps.

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Useful for toggling between:

• NA / Nitrous
• Low Boost Cut/ High Boost Cut levels for the track
• Fuel economy/ performance
• Vtec maps with non vtec ecu / ecu codebase
• warm/cold weather maps