All WDC datasheets that I've seen say, W65c02S is a 14 MHz device. I would never known about the 10 MHz version, but I had bought it. I believe that AC characteristics should also be different, but how to get them? Does anyone have this information?
Thanks.
W65C02S8P-10 AC characteristics
- GARTHWILSON
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Re: W65C02S8P-10 AC characteristics
Are you looking for the timing specifications for an older 10MHz version? I don't have those; but the current (14MHz+) data sheets are on the manufacturer's website, at http://westerndesigncenter.com/wdc/documentation.cfm .
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?
Re: W65C02S8P-10 AC characteristics
In anothter topic (viewtopic.php?t=511) I read:
What do you mean by saying 'On my older one...' ?
GARTHWILSON wrote:
Doggone, you're right! I never noticed that. It definitely is an error, and I expect it crept in because of the 65816 which has no phase-2 output. It wouldn't be the first time someone found an error in their WDC's diagrams and spec.s. Which data sheet did you look at? On my older one, it has a delay of up to 40ns from phase-2 input to phase-2 output even for the 10MHz part, and then they reference everything to the input; but 40ns is almost as long as the clock is either high or low, so obviously that won't fly. I looked at a newer data sheet though, and it was fixed.
The phase-2 input and phase-1 output seem to be primarily intended for hanging a crystal or an RC right on the processor itself so an external oscillator is not always needed. It wouldn't make sense to connect the actual processor's innards to the phase-2 input since that one is a Schmitt-trigger input specifically so it can handle the slowly ramping voltage you'd get from a capacitor and resistor connected directly for using the onboard oscillator.
The phase-2 input and phase-1 output seem to be primarily intended for hanging a crystal or an RC right on the processor itself so an external oscillator is not always needed. It wouldn't make sense to connect the actual processor's innards to the phase-2 input since that one is a Schmitt-trigger input specifically so it can handle the slowly ramping voltage you'd get from a capacitor and resistor connected directly for using the onboard oscillator.
- GARTHWILSON
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Re: W65C02S8P-10 AC characteristics
Quote:
What do you mean by saying 'On my older one...' ?
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?
Re: W65C02S8P-10 AC characteristics
Thank you Garth, this is just what I need... 
Re: W65C02S8P-10 AC characteristics
Reviving a dead thread as I have a 65C02S in my hands here. UMC branded W65C02S8P-10 to be exact.
Code wasn't working as expecting, so I did some debugging. It seems this UMC produced variant does not support the 65C02 additional op codes. I have tested PHX PHY PLX PLY STP BRA and none work. Not an assembler issue, I have pushed the op codes directly into memory and executed.
Back to nmos op code set I go!
Edit: looking closer at the chip, the date code is 0119S, but I bought the chip in late 2017/early 2018 .... EBay China strikes again.
Code wasn't working as expecting, so I did some debugging. It seems this UMC produced variant does not support the 65C02 additional op codes. I have tested PHX PHY PLX PLY STP BRA and none work. Not an assembler issue, I have pushed the op codes directly into memory and executed.
Back to nmos op code set I go!
Edit: looking closer at the chip, the date code is 0119S, but I bought the chip in late 2017/early 2018 .... EBay China strikes again.
Re: W65C02S8P-10 AC characteristics
Hmm, surely a fake, according to this:
Quote:
The 'UMC' logo on chips together with 'W65C02..' is a giveaway here - there's no W65C02 produced by UMC.
Re: W65C02S8P-10 AC characteristics
Thanks for the link.
Solves a lot of weird quirks with my code, knowing that I can't use 65C02 op codes.
Solves a lot of weird quirks with my code, knowing that I can't use 65C02 op codes.
Re: W65C02S8P-10 AC characteristics
Yes, the UMC real chips used 'UM' as a prefix, not 'W' - afaik only WDC use W.