Flex6K configuration PROM

[snip]


I had similar problem - ADI development board for high speed ADC has
Flex6K on the board and I needed to change the config - and found the
same story as you - no known solution from Altera, and even though
Atmel config roms claim Altera compatibility not clear if Atmel rom
would work with Flex 6K.

solutions: for Flex 6K, use cheap serial eeprom (ISSI or other) and cheap
8 pin microcontroller to boot up the serial eeprom, hmm for some smaller
densities some serial eeproms could be used without that micro also,
there was a mailing about this here some time ago

use parallal flash and cheap pld to config
use some micro with enough internal flash to get the config

use some other part - this is probably best solution.
there are many FPGAs in tqfp 100 and some should be cheap as well
APA075 is 17USD qty one (non volatile FPGA, no confi mem)
small XC2S are about 9USD qty 1
hm not sure if cyclone comes in tqgp100

but really if there is no special reason to use flex 6k DO NOT USE it

antti
http://www.graphord.com/forum

Thanks for the response Antti.

snipped-for-privacy@case2000.com says...



Yes, I guess I'll have to investigate those more indepth.



Phyiscal space is a big problem in this case, otherwise a cheap FlashROM
and uC would do the trick perfectly.
 


I am limited by two factors:

1. FPGA must *run* on 3.3V (not just be 3.3V compliant)
2. FPGA should be in 100-pin TQFP or smaller (smaller the better,
without resorting to BGA / CSP)

While most of the FPGAs have 3.3V I/O, they run on <=2.5V , which I
can't accomodate. The APA075 looks good but it also needs a 2.5V VDD.

As an aside, are the software design tools for the APA075 free/cheap ,
and what distributor did you get the pricing from?

Thanks!
Jay.

Why can't you generate a 2.5 volt power supply?  You could probably get
away with a PN diode in the SOD-323 package and a 1K pulldown resistor
(to establish a minimum current) to drop the 3.3 volts to 2.6 volts.
The Altera EP1K10TC100 (ACEX 1K) would be perfect.

Daniel Lang

Just to follow up a bit on my own thread, the "cheap" ISP alternative
wasn't from ISSI, it was from SST. Here's the Google thread:

http://tinyurl.com/mbjl

Now, let's see if we can get that configuration PROM to work with an
Altera FPGA w/o resorting to an 8-pin uC.

Thanks,
Jay.

Just in case tinyurl ever goes away, here's the very long link split
over sveral lines, for the benfit of future generations :-)

http://www.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8 &
threadm=pan.2003.03.17.13.09.48.115606.23961%40
freeby.mesanet.com&rnum=8&prev=/groups%3Fq%3DEEPROM%2B
group:comp.arch.fpga%26hl%3Den%26lr%3D%26ie%3DUTF-8%26oe%3D
UTF-8%26selm%3Dpan.2003.03.17.13.09.48.115606.23961
%2540freeby.mesanet.com%26rnum%3D8

I used one a long time ago with a 6016A, worked fine.  What makes you
think they won't work?



The Altera ones were about £20 last time I bought them. :-(

HTH,
Martin

Hi Martin,

Thanks for your response.



Are you sure it was an EPC2?

They make mention several times not to use it on the Flex 6K family:

http://www.altera.com/literature/ds/dsconf.pdf , page 9, note 1:

"Do not use EPC2 devices to configure FLEX 6000 devices." , and again on20%
page 12, etc.

I'm wondering why the Altera guys haven't followed up in the NG, they20%
seem to be pretty attentive as of late.



That doesn't sound too promising. How much were you paying for the20%
EPF6016As, if I might ask?

Thanks,
Jay.

Yep, I reprogrammed it and everything!



So they do, I hadnot noticed that!  I was going on the fact that they
"seemed" to be compatible with the older EPC1x series in terms of
pinout and timing.  Indeed, table 5 is entitled "Table 4. APEX 20K,
FLEX 10K & FLEX 6000 Timing Parameters using EPC2 Devices at 3.3 V"



Yeah, they would have the "right" answer, but I can certainly say it
worked for us.  We made a few of these boxes, and some of them ended
up on the front of cars, and I never had any complaints.



Sorry, Ijust poked around our Purchase database and can't find any
record of them.  I think we must have bought them from a different
supplier to usual :-(  The EPC2s were there though, 18UKP.

Hope you get some official answers!

Cheers,
Martin

Hi Martin,

Thanks for the info. I'll keep the group apraised of what I do.

Right now it looks like one of those SST parts with a uC helper. I
really don't see why a config ROM should cost so much (more than an
FPGA?)

Still no word from Altera (via e-mail or NG) though.

Thanks,
Jay.

I have used ATMEL parts - they're much cheaper and reprogrammable.

for price comparison only, look at www.ebv.com (German distributor, has both
Atmel
and Altera) - they have price list search on-line...

regards

Dejan