| Posted By
SVS
on 2002-05-13
 |  I have to read the code of a banked Rom,
please confirm me if it's sufficient to set Rom on TED, and to write in $FDDx the bank number ($0, $5, $A, or $F), before to execute the LDA operation.
If yes, have I to redo the writing on $FDDx for the following reading operations?
Thank you boys.
S\_/S
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Posted By
Gaia
on 2002-05-13
| It's enough
It is enough to switch on the ROM bank once. Note however, that area $FC00-$FCFF will always be read from the first bank (C0 HIGH) as it contains the IRQ handler (among others).
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Posted By
BushRat
on 2002-05-13
| Yup
Just caught this message...Attila is right, of course. What rom are you trying to grab? Used to just dump it to Ram under the Rom then change $07f8 to $80 to save or look at it.Then load $07f8 with $00 to restore looking at Rom.
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Posted By
SVS
on 2002-05-14
| Thank you for yr replies,
I was informed a boy owns a Plus4 "Canadian version". He told me it has Roms different than a normal +4. So I encouraged him to save them into files, in order to examinate them with an emulator.
Unfortunately the resulting files was corrupted and not loadable. Then I have the way to send to him a program to copy the Roms' content on disk from the real Canadian Plus4.
Attila: Can I read and then save the content of $FC00..$FCFF whatever it is, in the Rom' image file? (or have I to fill with $00 or $FF?9. If this segment would be never used, I think it can be everything, OK?
Jim: I think that by Monitor it's not possible to view a Rom different than the system Roms (bank $00). $7f8 only allows to swap Rom-Ram, isn't? Or after setting $FDDx it could show alternative Roms? 
Thank you boys.
S\_/S
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