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Re: Single step (ram) with BRK
Posted: Fri Feb 17, 2023 8:54 pm
by barnacle
Hmm, that's something I had not considered. Time for a rethink
Neil
Re: Single step (ram) with BRK
Posted: Wed Feb 22, 2023 8:16 am
by rudla.kudla
You will probably also need to print a list of all currently defined breakpoints and allow clearing some of them.
The best option probably is to have a list of breakpoint addresses and search a breakpoint based on it's address. The same table will contain the code of the instruction you replaced with BRK.
Re: Single step (ram) with BRK
Posted: Wed Feb 22, 2023 5:03 pm
by Dietrich
You might want to have a look on my DEBUG.COM, which offers most of the discussed features with the notable exception of stepping through ROM code. The program uses the BRK method and enables to set up tp 8 breakpoints [0..7]. The source can be found here:
https://github.com/Dietrich-L/CPM-65/bl ... /DEBUG.ASM
Command syntax :
Code: Select all
DEBUG V1.7 (c) 14.6.1990
Command Summary:
Dnnnn,mmmm dump memory Fnnnn,mmmm,cc fill memory
Gnnnn go from nnnn Znn wait for nn/10 s
Lnnnn,mmmm list mnemonics Ennnn,bb,bb.. enter bytes
Rfilename.ext read file Wfilename.ext write file
Nfilename.ext FCB1=filename
Cnnnn,<string> enter string Snnnn,mmmm,bb,.. search bytes
Tdd trace dd steps Xr,bb set register
Jdd jump dd opcodes Mn,m,j move to n from m,j
Bd,nnnn set breakpoint Kd kill breakpoint
? prints this screen ; command separator
/dd repeat dd times Q quit to CP/M
The progam installs itself in high memory at $C000, the code to be analyzed can be anywhere in the available RAM.
Enjoy
Dietrich