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AppleWin softswitch to HGR2 on //e emulation? ($C055)

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Hot Rod

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Sep 3, 2012, 9:18:17 AM9/3/12
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Hello,

When I boot AppleWin (1.20.0) while emulating an Apple //e (regular, not enhanced) and try to access hi-res page 2:

]CALL -151

*C050

*C057

*C055

It seems to always stay on hi-res page 1 instead. When I boot a program that does HGR2 and loads a picture into $4000, I also notice that it doesn't display it, but stays on page 1 instead.

If I switch to emulating an enhanced Apple //e, it works fine.

If I switch to emulating an Apple ][+, it works fine.

That suggests that something is amiss in the $C055 softswitch for the Apple //e emulation?

]HR


BLuRry

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Sep 3, 2012, 10:54:52 AM9/3/12
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Is it misinterpreting the 80store switch? What if you explicitly set 80store off (c000:0) before trying to flip to page2?

-B

Hot Rod

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Sep 3, 2012, 7:08:00 PM9/3/12
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On Monday, September 3, 2012 9:54:52 AM UTC-5, BLuRry wrote:
> Is it misinterpreting the 80store switch? What if you explicitly set 80store off (c000:0) before trying to flip to page2?
>
>
>
> -B
>

I tried that, and it doesn't seem to have any effect; still doesn't flip to page2.

Michael J. Mahon

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Sep 3, 2012, 10:08:55 PM9/3/12
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I always go into 40-column mode by PRINTing CHR$(21) before doing an HGR2
in AppleSoft. Otherwise, it doesn't switch.

Unfortunately, I've never taken the time to determine exactly why. ;-(

-michael - NadaNet 3.1 and AppleCrate II: http://home.comcast.net/~mjmahon

Hot Rod

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Sep 3, 2012, 10:51:34 PM9/3/12
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On Monday, September 3, 2012 9:08:56 PM UTC-5, Michael J. Mahon wrote:
>
> I always go into 40-column mode by PRINTing CHR$(21) before doing an HGR2
>
> in AppleSoft. Otherwise, it doesn't switch.
>
>
>
> Unfortunately, I've never taken the time to determine exactly why. ;-(
>
>
>
> -michael - NadaNet 3.1 and AppleCrate II: http://home.comcast.net/~mjmahon

That doesn't work either (with AppleWin emulating a //e). Still doesn't switch to page2. I just use Enhanced //e or ][+ emulation for now instead.


TomCh

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Sep 16, 2012, 3:31:57 PM9/16/12
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In //e mode, I see a flash of HGR page2 before it switches back to page1.

But this works:
]CALL -151
*300: AD 50 C0 AD 57 C0 AD 55 C0 4C 9 3

So it must be something in the firmware that is switching back to page1.

Tom

Hot Rod

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Sep 16, 2012, 5:41:28 PM9/16/12
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That's interesting. Running that code does indeed get to page 2. However, if I just access the softswitch addresses directly from monitor:

]CALL -151

*C050

*C057

*C055

It does not display page 2 when emulating an Apple //e. This does work when emulating a ][+ or enhanced //e.

Kinda odd.

Michael J. Mahon

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Sep 17, 2012, 12:15:09 AM9/17/12
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If you're in 80-column mode, any output to the screen (like a prompt) will
twitch 80store.

TomCh

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Sep 17, 2012, 3:48:00 PM9/17/12
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Just set a BP on $C054... there must be something in the firmware ($C100..$CFFF) that accesses this during the CIN / COUT (and other) routines.

ie:
]CALL-151
F7 to enter AppleWin's debugger
>BPM c054
>g
*C055<CR>

This hits 3 times at $CB45: STA SW.LOWSCR

Interestingly, just pressing RETURN from the monitor doesn't trigger this BP.

Also:
*C054<CR>

This hits at $FDBB: LDA (MON.A1L),Y ; Y=0
Then once at $CB45

---

Enhanced //e:

*C055<CR>
This doesn't hit the BP at $C054

Tom

aiia...@gmail.com

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Sep 26, 2012, 7:32:48 PM9/26/12
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On Monday, September 3, 2012 6:18:17 AM UTC-7, Hot Rod wrote:
> When I boot AppleWin (1.20.0) while emulating an Apple //e (regular, not enhanced) and try to access hi-res page 2:
>


i JUST RAN

aiia...@gmail.com

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Sep 26, 2012, 7:37:51 PM9/26/12
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On Monday, September 3, 2012 6:18:17 AM UTC-7, Hot Rod wrote:
> Hello,
>
>
>
> When I boot AppleWin (1.20.0) while emulating an Apple //e (regular, not enhanced) and try to access hi-res page 2:
>
>

i JUST ran into some weirdness with HGR2 with applewin as well...

Enhanced IIe mode

I had some code at $4000 that I wanted to clear out to zero... I was in PR#3 80 column mode.

]HGR2 (TWO)

it displays the hgr1 (ONE) screen ($2000, I verified this by doing 2000:FF FF in the monitor, it displays 14 lit pixels) and the HGR1 (ONE) screen is NOT cleared.



aiia...@gmail.com

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Sep 27, 2012, 12:01:29 PM9/27/12
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On Wednesday, September 26, 2012 4:37:52 PM UTC-7, (unknown) wrote:
> i JUST ran into some weirdness with HGR2 with applewin as well...


repeatable in 80 column mode (PR#3 from ] prompt)

If NOT in 80 column mode, HGR2 works as it should (display graphics from $4000, clear screen)

Rich


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