6510 vs 8500 - support for illegal opcodes ?

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eslapion
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6510 vs 8500 - support for illegal opcodes ?

Post by eslapion » Wed Jul 13, 2016 1:26 pm

It seems to be a well known fact that the 6510 supports the illegal op-codes of the MOS 6502, apparently a consequence of both having been made using NMOS process. It's also known that CMOS versions of the 6502, such as the popular Rockwell R65C02 do not support these op-codes.

But what about the 8500 which is a 6510 drop-in replacement made by MOS/CSG beginning in 1986 ? Does it support illegal 6502 op-codes too?

This CPU is 100% pin compatible with the 6510 and is used in many boards 250466 and the 64c's 250469. It was made using HMOS process technology which makes it consume a lot less power and produce virtually no heat. Does the change in manufacturing process have the same consequence as with the CMOS 6502 ?


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Re: 6510 vs 8500 - support for illegal opcodes ?

Post by tiny tim » Wed Jul 13, 2016 2:52 pm

At least the stable illegals and the "stable when used in a certain way" ones behave exactly the same.

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Re: 6510 vs 8500 - support for illegal opcodes ?

Post by eslapion » Wed Jul 13, 2016 3:19 pm

tiny tim wrote:At least the stable illegals and the "stable when used in a certain way" ones behave exactly the same.
Thanks!

Do you know of any specific notable difference(s) between the 6510 and 8500 from a programming point of view ?
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Re: 6510 vs 8500 - support for illegal opcodes ?

Post by dudz » Thu Jul 14, 2016 12:32 am

there is none, they behave exactly the same.

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Re: 6510 vs 8500 - support for illegal opcodes ?

Post by eslapion » Mon Jul 18, 2016 12:46 am

dudz wrote:there is none, they behave exactly the same.
Not sure I can buy that considering what you posted in other threads...
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Re: 6510 vs 8500 - support for illegal opcodes ?

Post by dudz » Sat Jul 23, 2016 6:00 pm

not sure if i give a damn, considering what you posted everywhere else.

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Re: 6510 vs 8500 - support for illegal opcodes ?

Post by eslapion » Sat Jul 23, 2016 7:15 pm

dudz wrote:not sure if i give a damn, considering what you posted everywhere else.
Oh My!...

Image
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Re: 6510 vs 8500 - support for illegal opcodes ?

Post by Gyro Gearloose » Sun Jul 24, 2016 12:16 am

Girls, girls, girls.. You're BOTH pretty. Now stop it.
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Re: 6510 vs 8500 - support for illegal opcodes ?

Post by tiny tim » Sun Jul 24, 2016 9:34 pm

^ this, or write test programs! :)

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Re: 6510 vs 8500 - support for illegal opcodes ?

Post by eslapion » Sun Jul 24, 2016 10:45 pm

tiny tim wrote:^ this, or write test programs! :)
Would be nice if I knew what to look for...
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