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Vic-II: Setting the address of the bitmap?
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Harry Potter
Jun 14, 2013, 8:55:38 AM6/14/13
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I have some documentation on the C64's and C128's IOs. They provide in sufficient detail most of the registers, but there are holes in the docs. One hole is that it doesn't give the register to determine whether the bitmap screen is at start VIC bank+$0000 or start VIC bank+$2000. Can anybody help me?
Payton Byrd
Jun 14, 2013, 2:01:56 PM6/14/13
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On Friday, June 14, 2013 7:55:38 AM UTC-5, Harry Potter wrote:
> I have some documentation on the C64's and C128's IOs. They provide in sufficient detail most of the registers, but there are holes in the docs. One hole is that it doesn't give the register to determine whether the bitmap screen is at start VIC bank+$0000 or start VIC bank+$2000. Can anybody help me?
RTFM
> I have some documentation on the C64's and C128's IOs. They provide in sufficient detail most of the registers, but there are holes in the docs. One hole is that it doesn't give the register to determine whether the bitmap screen is at start VIC bank+$0000 or start VIC bank+$2000. Can anybody help me?
wwww....@gmail.com
Jun 15, 2013, 9:28:18 AM6/15/13
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Groepaz
Jun 16, 2013, 2:08:34 PM6/16/13
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compilers you are using.
read up on $d018
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Harry Potter
Jun 21, 2013, 12:21:40 PM6/21/13
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On Sunday, June 16, 2013 2:08:34 PM UTC-4, Groepaz wrote:
> there is no hole in the documentation just as there are no bugs in the compilers you are using. read up on $d018
I just looked at my documentation. The entry on $D018 reads:
> there is no hole in the documentation just as there are no bugs in the compilers you are using. read up on $d018
---------------------
D018 53272 VIC Memory Control Register
7-4 Video Matrix Base Address (inside VIC)
3-1 Character Dot-Data Base Address (inside VIC)
0 Select upper/lower Character Set
---------------------
This doesn't show the setting for the address of the bitmapped graphics buffer.
Payton Byrd
Jun 21, 2013, 2:50:03 PM6/21/13
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From the C64 Programmer's Reference Guide page 101:
The BANK SELECT bits that allow you access to all the different sections of memory are located in the 6526 COMPLEX INTERFACE ADAPTER CHIP #2 (CIA #2).
Keep reading about 1 sentences later and it tells you to set bits 0 and 1 of register $DD00.
Where is the hole in the docs?
The BANK SELECT bits that allow you access to all the different sections of memory are located in the 6526 COMPLEX INTERFACE ADAPTER CHIP #2 (CIA #2).
Keep reading about 1 sentences later and it tells you to set bits 0 and 1 of register $DD00.
Where is the hole in the docs?
Groepaz
Jun 22, 2013, 9:41:31 AM6/22/13
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essentially the same as character mode, so the character base address is the
same as the bitmap base address. (also your docs suck, its bit 3-0 that
select the character base)
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Harry Potter
Jun 24, 2013, 9:06:42 AM6/24/13
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So $D018, bits 4-7, specify the address of the bitmap buffer. I assume it has a gradient of 1k (i.e. 0000=bank+0k, 0001=bank+1k, etc.). I also recall the address of the VIC-II bank in one of the CIAs. I don't remember where, and, for some reason, the bits seem to be reversed (i.e. 11=bank at $0000). Thank you! :)
Payton Byrd
Jun 24, 2013, 12:04:43 PM6/24/13
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On Monday, June 24, 2013 8:06:42 AM UTC-5, Harry Potter wrote:
> So $D018, bits 4-7, specify the address of the bitmap buffer. I assume it has a gradient of 1k (i.e. 0000=bank+0k, 0001=bank+1k, etc.). I also recall the address of the VIC-II bank in one of the CIAs. I don't remember where, and, for some reason, the bits seem to be reversed (i.e. 11=bank at $0000). Thank you! :)
Can you not read? I posted the exact info about the CIAs to this thread.
> So $D018, bits 4-7, specify the address of the bitmap buffer. I assume it has a gradient of 1k (i.e. 0000=bank+0k, 0001=bank+1k, etc.). I also recall the address of the VIC-II bank in one of the CIAs. I don't remember where, and, for some reason, the bits seem to be reversed (i.e. 11=bank at $0000). Thank you! :)
Harry Potter
Jun 24, 2013, 12:22:08 PM6/24/13
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On Monday, June 24, 2013 12:04:43 PM UTC-4, Payton Byrd wrote:
> Can you not read? I posted the exact info about the CIAs to this thread.
I'm sorry. I didn't say it correctly. :( I meant to imply that I already have the info on the VIC-II Bank # and can look at it.
> Can you not read? I posted the exact info about the CIAs to this thread.
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