Ricardo, try apatco, the store that posted above. viewtopic.php?t=1623&start=26 will put their post at the top of the page. (I have not yet looked into their shipping rates myself though.)

Shipping is going to be high unless from a source within Venezuela. I ran your locale through both our FedEx and UPS shipping tables and they were right around 50 dollars, not counting insurance. In fact, shipping the same amount of weight to neighboring Guyana is less expensive. I suspect political considerations may be a factor.

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

Yes, the private carriers are very expensive for shipping to other countries. The post office is much cheaper, but then you have to worry about the inefficiency, carelessness, and theft of some countries' postal systems. For these parts you could weigh the percentage of risk (if you have a good idea of what that level is) and decide if it's worth it. A few weeks ago I sent a board to someone in Australia through the post office, and it cost $9 and reached him in three days.

Australia isn't exactly a political enemy of the United States though, and commerce with them is quite regular. I tend to agree with BDD here, you're going to find postal rates and/or loss are insane because of political issues.

Private carrier is far safer than postal, even when going to a friendly destination like Down Under. Once you add on all the necessary safeguards to parcel post (e.g., insurance, tracking, etc.) the cost gets close to that of private carriers. You still, however, have the risk associated with a government-run operation.

In any case, FedEx and UPS are both substantially cheaper from my location to Sydney than to Caracas, even though the latter is a lot closer. There's no question that politics has much more to do with the shipping rates to Venezuela than the cost of operating a cargo plane.

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

WDC says that the $50 rate is for all international shipping no matter what country. I will copy it here:
" All small (under $100) domestic orders will be shipped UPS Ground and charged a flat rate of $7.50 plus a $10.00 handling charge.. All orders are shipped FOB WDC Mesa AZ. Sales tax will be added to orders within Arizona. International orders are shipped US Global Priority Mail and charged a flat rate of $25.00. An additional $15.00 charge will be added for handling of International order".
So i do not believe it is because political reasons. It is just a rate that the company charges. I will write to apatco to see their answer.

Finaly i got the W65C02S6TPG-14 and i could rise the clock from 5 Mhz to 10 Mhz the old G65SC02 could not do it. Believe it or not is working with a 100 ns RAM. Don't ask me why. The problem that i am getting now is when i use the software in the EPROM (V 10 Mhz) for working at 10 Mhz does not run properly. But when i run it at 5 Mhz it does ok but from time to time i get some garbage. I take the RAM out for some minutes and i put it back to take away the garbage. I have other EPROM that has a 5 Mhz version (V 1.1) and it runs ok at 10 Mhz. I put a faster RAM and the problem still goes on.

Let me recapitulate the tests i have done:


# - CPU (MHz) - RAM (ns) - EPROM version - Works ?
--------------------------------------------------------------------
1 - 10 - 100 - 1.1 - ok
2 - 10 - 70 - 1.1 - ok
3 - 10 - 70 - 10 - wrong LED flashing
4 - 5 - 70 - 10 - ok (but some garbage from time to time)
--------------------------------------------------------------------

could this be an EPROM (V 10 Mhz) problem?

best regards
Ricardo

It is guaranteed to be no worse than 100ns at the worst voltage (4.75V?) and worst temperature (the hottest specified). Usually it will be better than 100ns even under those conditions, and better yet at 5V and room temperature.

See my PM about how to get your columns to line up.

I am upgrading my 5 Mhz chess system to 10 Mhz. For this i have the following IC:

CPU 10 Mhz W65C02S6TPG-14
RAM WS6264LLPG-70 (70 ns)
EPROM 27C512 loaded with 10 Mhz version
10 Mhz crystal.

The 5 Mhz module has the following IC:

CPU 5 Mhz G65SC02
RAM SRM2264 LC-10 (100 ns)
EPROM 27C512 loaded with the 1.1 version
4.9 Mhz crystal

I have done the following tests:






To solve this garbage issue i take the RAM out for some minutes and then put it back in. The board has a battery but i do not take it out because is weld it.

1)Why is this garbage?
2)Why the configuration # 3 does not work (V 10 Mhz) and it does work at 10 Mhz with (1.1) version?.

4)Could this be an EPROM (V 10 Mhz) problem?

5) Is it a power supply problem?



Best regards
Ricardo

Do the W65C02S6PG-14 CPU has the same instruccion set than the W65C02S6TPG-14 CPU. Because there is another person that told me that he has the same project than me and it works and the only diference is tha he has the W65C02S6PG-14 CPU.

The "T" in the part number seems to have something to do with the wafer-fab process. The instructions would be the same.

Sounds like there's a timing marginality. Changing the power supply voltage and the clock frequency by small amounts might help to see what goes wrong and why. A logic analyser would help too, or a scope. But I appreciate that you might not have the equipment for those investigations.

You have two EPROMs with different versions of the chess program, I think. Are these two EPROMs the same part number - the same electrical and timing characteristics?

Thanks GARTHWILSON and BigEd for the answers.
Your right BigEd i do not have a logic analyser or a scope.
it is also right that i have two diferent version of the same chess program V 1.1 and V 10 on each EPROM.

If you see the chart, about 4 post above that kindly GARTHWILSON rearrange for me you can see that the configuration number 1 ran at 10 Mhz with no problem so i do not think it is a frecuency problem (it even ran ok with a 100 ns RAM).
Then i test the other version (V 10) in the configuration number 3 and did not work (wrong led flashing). Then i lower the frecuency to 5 Mhz and change the CPU to the G65SC02 and the V 10 software ran ok (configuration mumber 4). I also made a configuration 5 test with the W65C02S6PG-14 CPU and the V 10 EPROM (sorry it is not in the chart) at 5 Mhz and it did not run either. Configuration number 1, 2 and 3 were all made with the W65C02S6PG-14.

best regards
Ricardo

One possibility to consider is that some I/O devices take a finite amount of time to respond to I/O requests. If the V10 software hits the I/O hardware faster than V1.1, it might not give enough time for signals to settle, which could perhaps yield garbage. This might explain why things "usually" work with 5MHz, but not 10MHz.

Thanks kc5tja for your answer,
But why the 10 Mhz software version runs at 5 Mhz with the G65SC02 CPU and it does not run with the W65C02S6PG-14 CPU.

best regards
Ricardo