The MOS Technology 6509, an enhanced version of the popular
6502 microprocessor
A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circu ...
, is capable of addressing up to 1
megabyte
The megabyte is a multiple of the unit byte for digital information. Its recommended unit symbol is MB. The unit prefix ''mega'' is a multiplier of (106) in the International System of Units (SI). Therefore, one megabyte is one million bytes o ...
of
RAM via
bank switching. While numerous 6502-based processors can perform bank switching, they achieve this via separate logic. The 6509 has this logic on-
chip.
The 6509 has a reputation for being difficult to program, due to its bank switching scheme. It is used in the
Commodore CBM-II
The Commodore CBM-II series is a short-lived range of 8-bit personal computers from Commodore Business Machines (CBM), released in 1982 and intended as a follow-on to the Commodore PET series.
Technical description
The CBM-II has two incarnati ...
line of computers.
References
Further reading
External links
MOS 6509 datasheet (GIF format, zipped)MOS 6509 datasheet (PDF format)
65xx microprocessors
MOS Technology microprocessors
8-bit microprocessors
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