How to go back one step with the debugger using Devpac-3?

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Robbizz
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How to go back one step with the debugger using Devpac-3?

Post by Robbizz »

Hi Guys, I use the step-by-step debugger to parse assembly instructions using Ctrl + Z. Now, sometimes I need to go back to the previous step. Isn't there a key combination on Devpac to do this?
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saulot
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Re: How to go back one step with the debugger using Devpac-3?

Post by saulot »

no, but you should have register history. back tracking/reverse debugging showed up in gdb ~2009, so forget it on Atari..
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Grazey / PHF
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Re: How to go back one step with the debugger using Devpac-3?

Post by Grazey / PHF »

No, as far as I know the only way to go back is to set the program counter (PC) to the desired address with ALT-R

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Re: How to go back one step with the debugger using Devpac-3?

Post by Zippy »

No shortcut that I'm aware of, I used to just position the address/instruction I wanted to go to at the top of the disassembly window and then ALT R and enter "PC=M2" to set the PC to that address.
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Re: How to go back one step with the debugger using Devpac-3?

Post by Robbizz »

I didn't think I could change the PC! Great idea! Thank you.
Oh I forgot, probably some of you are already aware of this thing but I would like to write it ..
you never know.
I needed to often read the contents of the stack, so I had to go to the memory window and press Alt + A and then type the address associated with the stack. A real waste of time. I found that the combination of Alt + A just type a7 which takes you directly to the memory where it points at that moment.
I think I discovered hot water :-D At least in my part they say so!
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Re: How to go back one step with the debugger using Devpac-3?

Post by Zippy »

You can also lock the memory window to a register, eg. ALT + L and enter A7 to lock it to the stack, so it automatically updates to the new address as the register value changes.
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Re: How to go back one step with the debugger using Devpac-3?

Post by mikro »

Thanks Zippy, I had no idea!
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Grazey / PHF
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Re: How to go back one step with the debugger using Devpac-3?

Post by Grazey / PHF »

Alt L is so useful. Especially when ripping music and the driver uses offset memory addressing :)

I should look at adebug sometime is it Monst with extra features?

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Re: How to go back one step with the debugger using Devpac-3?

Post by Zippy »

All I really used was the basic MonST and Dmon (for analysing and ripping special format disks), never used Adebug or Easy Rider or the hacked MonST versions or whatever, so not really sure what they were like.

The main change I remember making a real difference was when a new version of MonST was released and it had the search by instruction feature ("G" then "I" commands, basically searching for text within the disassembly window), that was SO useful for finding checksums 'cause you could search for partial instructions like "EOR.W (A" or "ADD.B (A" or just "(A0)+" or ",D0" if you knew they were using certain registers for the checksum but the actual calculation code was spread out all over the place.

It's funny how even now 30 years later I can drop right back into MonST and remember every keyboard shortcut, they are totally burned into my brain. :)
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Re: How to go back one step with the debugger using Devpac-3?

Post by mlynn1974 »

+1 for Alt+L. Brilliant!
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