exxos's Atari, Amiga & retro forum

I have these if they still work? They are 10s
P.s. ignore that dodgy soldering, I never got round to finishing them.

PhilC wrote: 18 Mar 2025 18:25 I have these if they still work? They are 10s

10ns seems to be pushing all the timings still :( I will have to build and test with the 6ns ones, then maybe move to a -10 and see what happens... But Grok claims 10ns is like 2-3ns to slow for proper SDRAM timings :(

exxos wrote: 18 Mar 2025 17:58 The 288-6 is about $49 a pop at JLC. Waiting for a quote currently.

I also asked my sourcing company for a price for 100 of them. See if there are any better deals anywhere but that unfortunately then leads to limiting to UK assembly.. Which could actually increase costs in particular on small batches :roll:

At that price it might be worth considering to abandon 5V tolerance and use a modern device with level shifters. Just for the sake of comparison, a MAX10 10M02 costs around U$ 8 if you buy 25 units. And this has almost ten times as much registers, let alone other features like PLL (trust me, a PLL can be invaluable for SDRAM), internal RAM, etc. You might even get cheaper devices.

Of course, it would complicate the hardware design. Just an idea.

Yeah worth considering, but like you say, it be a huge hardware redesign. It took me basically 2 years to get the current board done :( but it's also the price of loads of buffers which adds costs.. plus larger PCB.. It could force me onto a 6 layer board asnwell..it could still be cheaper in the end.. but it's a lot of work just to save the buyer a bit on the price ultimately.

Jlcpb just told me the 6ns chips and SDRAM will take at least 19 days to obtain :roll: everything just takes way to long to get anything done these days :roll:

The only thing I could do is order the boards without the PLD and get the PLD off evilbay and hope it's not fake :roll:

exxos wrote: 19 Mar 2025 10:08 Jlcpb just told me the 6ns chips and SDRAM will take at least 19 days to obtain :roll: everything just takes way to long to get anything done these days :roll:

The only thing I could do is order the boards without the PLD and get the PLD off evilbay and hope it's not fake :roll:

The original TF536 used the 10s, are you sure you'd not like to try those as well?

PhilC wrote: 19 Mar 2025 10:30 The original TF536 used the 10s, are you sure you'd not like to try those as well?

I am currently using the 10ns , unless you mean the TF536 uses 288 10ns ?

exxos wrote: 19 Mar 2025 10:40

PhilC wrote: 19 Mar 2025 10:30 The original TF536 used the 10s, are you sure you'd not like to try those as well?

I am currently using the 10ns , unless you mean the TF536 uses 288 10ns ?

yes the TF536 uses 288 10s

PhilC wrote: 19 Mar 2025 10:41 yes the TF536 uses 288 10s

Oh thought they used the 144 for some reason.. But yeah the timings change each compile and it seems borderline at best. In order to satisfy the SDRAM timings , a 6ns has to be used :( 10ns could be tried, but I'd need to do everything "by the book" to start with... But all the testing involved... Not sure it's worth testing 5ns then doing it all again with 10ns.. even if 10ns worked on my ST, it may fail for someone else, just down to tollerences..

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