Title: ROM (in RAM) Reset Patch v1.0
Author: Steve Evans (Zephyr)
Publisher: Steve Evans (2025)
Platform: Dragon 64, 64K Dragon 32, and 64K Tandy TRS-80 Color Computer

Released by Steve Evans (zephyr) https://archive.worldofdragon.org/
Release Date: 21st of January, 2025


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 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. 

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.

Enter POKE113,254:EXEC to select "copy only mode". The "copy only mode" copies all ROM locations ($8000 to $FEFF) to RAM without applying any patches.


After the ROM (in RAM) has been patched:

Enter POKE&H71,0:EXEC&HB3B4 or POKE113,0:EXEC46004 on a Dragon 32/64 for a full cold start without reverting back to ROM mode.

Enter EXEC&HB3B4 or EXEC46004 (or press the reset button) on a Dragon 32/64 for a warm start without reverting back to ROM mode.

Enter POKE&H71,0:EXEC&HA027 or POKE113,0:EXEC40999 on a CoCo 1/2 for a full cold start without reverting back to ROM mode.

Enter EXEC&HA027 or EXEC40999 (or press the reset button) on a CoCo 1/2 for a warm start without reverting back to ROM mode.


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.

Enter EXEC&H10F or EXEC271 to start any FIRQ auto-starting cartridges.

Enter EXEC&HC002 or EXEC49154 to start any DOS type cartridges.


Steve Evans (zephyr)
https://archive.worldofdragon.org