Viewing banks with emu debugger / MON command

ZeroByte · Post by **ZeroByte** » Sat Mar 13, 2021 3:22 pm

I've spent time needlessly banging my head against a wall here. I'm starting to learn to work with the banked RAM. So I wrote a routine to load stuff into hi memory, and then wanted to go into MON or the debugger just to see that this was successful. I read that MON uses Oxx to set the RAM bank, and the debugger uses B RAM xx to set the RAM bank. However, when doing either of these, I see the same seemingly random data over and over when I then do MA000 A0FF.

I'm guessing that I'm only ever seeing bank0 which the Kernal/BASIC use, and never the actual data.

Realizing that it must be user error, I decided to just bang out a quickie BASIC program to poke predictable values into the banks and then peek them back out again - this confirms that my banking is in fact working, but I still can't figure out what I'm doing wrong with my debug tools.

Q: In debugger, when I set, e.g.: B RAM 4 - does this cause the actual RAM bank to switch to 4 in the system? What about MON?

What commands should I use to just view the contents of the banks, but not actually meddle with the system state?

JimmyDansbo · Post by **JimmyDansbo** » Sat Mar 13, 2021 3:33 pm

In the debugger, you just do: DbankADDR so something like D4A000 will show code at address $A000 in bank 4.

M4A000 would show the memory contents of $A000 in bank 4

ZeroByte · Post by **ZeroByte** » Sat Mar 13, 2021 3:48 pm

I was just re-visiting the thread where you're discussing this topic but regarding the debug output when jumping into the kernal load API - this info wasn't explicit (or I missed it) but your screenshots gave me the clue I needed to get the debugger to show what I want. I just figured this syntax out and was about to come close my own thread lol.

But while we're at it, do you know the equivalent commands in the monitor (or do they not exist yet)?

Thanks for replying here!

JimmyDansbo · Post by **JimmyDansbo** » Sat Mar 13, 2021 3:50 pm

1 minute ago, ZeroByte said:

But while we're at it, do you know the equivalent commands in the monitor

I have no clue on how to use the monitor...

x16tial · Post by **x16tial** » Sat Mar 13, 2021 5:53 pm

In the monitor use oxx, and make sure it 's not a Shift-O (like if you're in lower case mode), and make sure you use BOTH digits, so bank 0 would be 'o00', 255 would be 'off' (use hex)

For inspecting vera memory use ov0 and ov1. o by itself will reset back to main memory bank 0

to summarize for the monitor

banks: o00 to off (switches both ram and rom banks)

vera: ov0 and ov1

o by itself: same as o00

(then use m to display whatever part of memory you're after)

pro tip: do a quick m 9f60, and the first two numbers will tell you what banks you're looking at (rom, ram)

(the rom bank is 0-7 and wraps around)

For the debugger:

the b command doesn't seem to work

but if you do m bbaaaa, it does, for example:

m 01a000

m 04c000

I haven't yet discovered how to display VERA memory in the debugger

derp, you guys already figured out the debugger above ?

JimmyDansbo · Post by **JimmyDansbo** » Sat Mar 13, 2021 6:23 pm

29 minutes ago, x16tial said:

I haven't yet discovered how to display VERA memory in the debugger

You just use V

v00000 = Address $0000 in bank 0

v10000 = Address $0000 in bank 1

x16tial · Post by **x16tial** » Sat Mar 13, 2021 6:24 pm

Just now, JimmyDansbo said:

You just use V

v00000 = Address $0000 in bank 0

v10000 = Address $0000 in bank 1

Ah, very nice!