41CL Calculator Manual
© 2019 Systemyde International Corporation
84
ALPHA
8040AC-883F
ALPHA
XEQ ALPHA
YPOKE
ALPHA
Enabling HEPAX Disassembly
The HEPAX
DISASM
function does not allow the disassembly of the HEPAX code
itself. If you want to remove this restriction, four locations in Bank 1 of the HEPAX code
need to be modified. The code is in Bank 1 of the HEPAX code, and we will use the
RAM at address 0x83E000 to hold the patched code.
First, the Bank 1 HEPAX image is copied to RAM:
ALPHA
02D>83E
ALPHA
XEQ ALPHA
YMCPY
ALPHA
Next, the instructions that branch to an error routine are replaced with NOP instructions:
ALPHA
83E131-0000
ALPHA
XEQ ALPHA
YPOKE
ALPHA
ALPHA
83E132-0000
ALPHA
XEQ ALPHA
YPOKE
ALPHA
ALPHA
83E133-0000
ALPHA
XEQ ALPHA
YPOKE
ALPHA
ALPHA
83E134-0000
ALPHA
XEQ ALPHA
YPOKE
ALPHA
Finally, this RAM page is substituted for bank 1 of the HEPAX image in Flash by directly
programming the MMU register:
ALPHA
8040A0-883E
ALPHA
XEQ ALPHA
YPOKE
ALPHA