Wrong address loaded into accumulator

[+Karl G]

I'm stumped on a bankswitching problem which amounts to be pushing the wrong address onto the stack, but I don't follow why the wrong address is being loaded.

 

As shown in the Stella debugger screenshot here, the address for the label "posttextkernel" here is $1F98 , and I'm trying to push (posttextkernel-1) onto the stack. Here is the snippet of source that does that:

        lda #>(posttextkernel-1)
        pha
        lda #<(posttextkernel-1)
        pha

As seen in the debugger screenshot, the first lda shows as "lda #$1F" as you would expect, but when I execute that line, I have $E0 in the accumulator instead of $1F.

 

Any ideas as to why/how this is happening?

 

[DirtyHairy]

I guess fast DPC+ fast fetch is active: in this mode, an immediate LDA of a value < 0x28 will not load the actual value, but the corresponding fetcher instead.

[+Karl G]

Oh! Indeed, I turned it on too soon. Thanks. :-)

[+SpiceWare]

You can confirm that in the debugger on the CartridgeDPC+ tab:

 

 

You might need to adjust the debugger window and/or font size to see it - I had to in order to take the above screenshot. Click on the Options... button at the top right to bring up the options menu:

 

Then click on Developer... and go to the Debugger Tab:

[+Karl G]

That's good to know for future reference - thanks!