ROM (in RAM) Reset Patch

[zephyr]

ROM (in RAM) Reset Patch v1.0

Copies the 16K BASIC System ROM to RAM, and patches the ROM (in RAM) to enable it to keep the computer running in 64K RAM (MAP1) mode, even after a software based full cold start reset (e.g. POKE&H71,0:EXEC&HB3B4 or MC: CLR $71 : JMP $B3B4). Pressing the hardware reset button will also result in the computer returning to 64K RAM mode. The only way to force the computer to go back to 32K mode (other than powering it off and on again), is to enter POKE&H71,0 (POKE113,0) and press the hardware reset button. Its main intended purpose is for running copies of cartridge based software which have been saved to cassette.

The optional "copy only mode" copies all ROM locations ($8000 to $FEFF) to RAM without applying any patches.

The patched ROM also has a routine which accurately emulates the FIRQ in order to be able to start any auto-starting cartridges without crashing the computer.

Two versions (Dragon and CoCo) are supplied. One is for a Dragon 64 or a Dragon 32 fitted with a 64K RAM upgrade. The other is for a Tandy TRS-80 Color Computer 1 or 2 with 64K of RAM and Extended Color BASIC.

The demo files I uploaded here (viewtopic.php?f=4&p=25676#p25676) are intended to be used on a real Dragon or CoCo after the ROM has been patched with my "ROM in RAM Reset Patch" program.

The following programs are intended for use with the ROM (in RAM) Reset Patch:

DragonDOS 64 viewtopic.php?f=7&t=11238
DragonDOS 64 NX01 viewtopic.php?f=7&t=11239
Cartridge Disable viewtopic.php?f=7&t=11236
CoCo Cartridge Disable viewtopic.php?f=7&t=11246
Cartridge ROM Size Detect viewtopic.php?f=7&t=11237