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BYTE Article of Mega II
- Subject: BYTE Article of Mega II
- From: "Bryan Parkoff" <nospam@nospam.com>
- Date: Fri, 11 May 2007 22:12:27 -0500
- Newsgroups: comp.sys.apple2
- Organization: Road Runner High Speed Online http://www.rr.com
- Reply-to: "Bryan Parkoff" <nospam@nospam.com>
- Xref: g2news1.google.com comp.sys.apple2:25849
Hello,
I read article at http://www.byte.com/art/9610/sec4/art2.htm. I have
one question.
The Mega II
The Mega II is a custom CMOS chip containing about 3000 gates and a 2K-byte
by 8 ROM (for the character generator). It replaces the fol lowing chips
from the Apple IIe and IIc: character generator ROMs for eight languages,
several TTL chips that perform logic functions, and the MMU (memory
management unit), IOU (input/output unit), TMG (timing generator), and GLU
(general logic unit) custom chips.
I stated earlier on the newsgroups. I know Mega II chip is ASIC type.
It has eight 2 KB ROMs or one 16 KB ROM holding eight languages of character
fonts. It is already had the answers how big ROM size can hold in the Mega
II chip. I doubt to say there are other ROMs like RGB matrix. It is to be
3,000 gates for MMU, IOU, TMG, and GLU.
I can't imagine how big 3,000 gates are. I wonder how did BYTE authors
know? Three thousands are like boolean logic to handle all functions. It
does handle RGB matrix to the output of four pins of RGB.
What do you think?
Bryan Parkoff