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Vic-II: Setting the address of the bitmap? [message #209951] Fri, 14 June 2013 08:55 Go to next message
Harry Potter is currently offline  Harry Potter
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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?
Re: Vic-II: Setting the address of the bitmap? [message #209954 is a reply to message #209951] Fri, 14 June 2013 14:01 Go to previous messageGo to next message
Payton Byrd is currently offline  Payton Byrd
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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
Re: Vic-II: Setting the address of the bitmap? [message #209956 is a reply to message #209951] Sat, 15 June 2013 09:28 Go to previous messageGo to next message
wwww.leser is currently offline  wwww.leser
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https://groups.google.com/forum/?fromgroups#!topic/comp.sys. cbm/p7owkelfs4s
Re: Vic-II: Setting the address of the bitmap? [message #209961 is a reply to message #209951] Sun, 16 June 2013 14:08 Go to previous messageGo to next message
Groepaz is currently offline  Groepaz
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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?

there is no hole in the documentation just as there are no bugs in the
compilers you are using.

read up on $d018

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Technology is dominated by two groups of people: 1) Those who understand
what they do not manage. 2) Those who manage what they do not understand.
Re: Vic-II: Setting the address of the bitmap? [message #209982 is a reply to message #209961] Fri, 21 June 2013 12:21 Go to previous messageGo to next message
Harry Potter is currently offline  Harry Potter
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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:
---------------------
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.
Re: Vic-II: Setting the address of the bitmap? [message #209983 is a reply to message #209982] Fri, 21 June 2013 14:50 Go to previous messageGo to next message
Payton Byrd is currently offline  Payton Byrd
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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?
Re: Vic-II: Setting the address of the bitmap? [message #209987 is a reply to message #209982] Sat, 22 June 2013 09:41 Go to previous messageGo to next message
Groepaz is currently offline  Groepaz
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Harry Potter wrote:

> 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:
> ---------------------
> 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.

yes it does, although not explicitly saying "bitmap". bitmap mode is
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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http://www.pokefinder.org http://ftp.pokefinder.org

"Virtual" means never knowing where your next byte is coming from.
Re: Vic-II: Setting the address of the bitmap? [message #209999 is a reply to message #209987] Mon, 24 June 2013 09:06 Go to previous messageGo to next message
Harry Potter is currently offline  Harry Potter
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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! :)
Re: Vic-II: Setting the address of the bitmap? [message #210003 is a reply to message #209999] Mon, 24 June 2013 12:04 Go to previous messageGo to next message
Payton Byrd is currently offline  Payton Byrd
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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.
Re: Vic-II: Setting the address of the bitmap? [message #210004 is a reply to message #210003] Mon, 24 June 2013 12:22 Go to previous message
Harry Potter is currently offline  Harry Potter
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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.
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