I'm trying to use the Mikro Assembler but keep having a most annoying bug with it.
Any immediate mode syntax error will make the visible screen text area jump down and right 25%, which makes reading the bottom right quarter of the screen not visible!
Anyone else seeing this behaviour? I have to type VERY carefully so as not to make a syntax error when I am typing commands. Most annoying.
I'm wondering if there is some pokes I can do to make the screen jump back to the default location, but a ROM with a fix for this bug would be awesome.
The ROM image I downloaded from Zimmers, and burned onto an EPROM, but the same behaviour happens when I run under VICE.
Mikro Assembler annoying bug!
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- Mike
- Herr VC
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Re: Mikro Assembler annoying bug!
Hint: PAL users are not affected.llcameron wrote:[...] Anyone else seeing this behaviour? [...] a ROM with a fix for this bug would be awesome. [...]

See point 2, "Incompatible by accident", in another thread.
No big deal to sort out if you're proficient with a monitor/debugger and know the VIC registers.
Re: Mikro Assembler annoying bug!
Awesome thank you for the link! I have wondered for the last 35 years what the differences between NTSC and PAL were and how to handle them correctly. !
Re: Mikro Assembler annoying bug!
Yes I see that this problem does not exist with a PAL VIC.
Are you aware of any magic pokes that can restore the screen back to its original NTSC position?
Are you aware of any magic pokes that can restore the screen back to its original NTSC position?
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- Vic 20 Hobbyist
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Re: Mikro Assembler annoying bug!
This will do the trick. I did a quick check of the program to see if I can find where it is changing the screen, but I can't find it as of yet.llcameron wrote:Yes I see that this problem does not exist with a PAL VIC.
Are you aware of any magic pokes that can restore the screen back to its original NTSC position?
The following will correct the screen though, should be dead center for NTSC.
Code: Select all
poke 36864,05
poke 36865,25
I don't see any reason why it wouldn't work on the vic 20(with a few small modifications perhaps)... I peeked into the book just to make sure, and yep, that's the book alright! It is called the LEA (Lothar Englisch Assembler, after the author of the book). It is apparently written in basic, and is a 2 pass assembler. The token part might need to be changed from c64 basic though...not sure.
http://69.60.118.202/books/commodore/bo ... ore_64.zip
...and you don't have to type it in apparently! Here is the disk containing the assembler and de-tokenizer
http://69.60.118.202/commodore/disks/books/ABACML64.D64
Re: Mikro Assembler annoying bug!
What I found is that a simple runstop/restore will return the screen back back to the center. Minor annoyance! Thanks for the suggestion!