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Posted By

KiCHY
on 2005-12-15
11:52:57
 That d*mned IRQ...

Hi!

Help! Help! I convert a program from C64 to Plussy and my IRQ doesnt want to work perfectly. Everything is fine at start, but after pressing some buttons and some code ran, all my raster effects (scroll, FF15 setting) goes down by 2 lines. At the same time the first two pixel rows of the characters at top of screen disappears, like the screen is turned off for that two line... Its weird for me, or i coded too long ago
I know that its hard to give a proper hint to "repair" this thing, but i remember i met this "disappearing of first two pixel rows" elarlier, in a multicolor fli effect or similar. I remember when I relocated the IRQ code of fli from $7xxx to $1xxx it went good...

Thx!

Posted By

indi
on 2005-12-15
15:18:19
 Re: That d*mned IRQ...

Sounds like vertical scrolling has been enabled. This will increase the top and bottom border. $ff06 or $ff07 (cant remember which off hand)

Posted By

KiCHY
on 2005-12-15
15:39:10
 Re: That d*mned IRQ...

Yeah I also got that idea and checked. No result. BTW not only the top of screen has this "effect". BTW I use 4 interrputs (all raster interrupt) for my effect (change background color and one scroll), and all interrupts slips two rows down. So when I start the app, the interrupts are in "good position", the scroll is fine, and soon i realize that the first two pixelrow of scrolltext jumps on characters instead of scrolling. I think you understand me... Trying expain with poor english skill

Posted By

Luca
on 2005-12-15
16:11:44
 Re: That d*mned IRQ...

Kichy, I'll suppose about, tought I'm absolutely not the right dude who should talk about interrupts in general.
Maybe your pressed-key routine is linked (BNE or BEQ) in a wrong way, and this causes something to the right IRQ screen splitting.
Ok, I'll shut up.

Posted By

Csabo
on 2005-12-15
21:02:45
 Re: That d*mned IRQ...

Why don't you post the source code? Someone may take the time and fiddle with it.

Also, did you try this on a real machine or on an emu? Could be an emulation bug rather than your code.

Posted By

KiCHY
on 2005-12-16
03:35:57
 Re: That d*mned IRQ...

Hurray!

I found the problem! MikeD was right... I didnt set ff06 directly only AND and OR, and I never touched bit 0-3 (vertical scrolling). I modified my code the set these to $1b (or $0b when screen is blanked) and my problem get solved. But its weird what sets those bits during running... Thanx for sugestions, etc Soon i publish it at Plus/4 World I hope Still in 2005.

Posted By

Luca
on 2005-12-16
08:40:58
 Re: That d*mned IRQ...

Ooooh!
Those are the cool news we like to hear!



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