[vdr] Re: [ANNOUNCE] Howto upgrade a full-featured dvb-s card to 4 MByte SDRAM

[Oliver Endriss <o.endriss@gmx.de>]

On Tuesday 15 June 2004 23:46, Joerg Schneide wrote:
> Oliver Endriss schrieb:
> > On Monday 14 June 2004 15:00, Joerg Schneide wrote:
> >>What is the maximum timing of the SDRAM-Chip?
> 
> > According to the data sheet, the SDRAM operates at 81 MHz clock
> > frequency. I suggest to use 10ns SDRAMs or better.
> 
> I asked because I found a 15ns chip on some scrap board,
> but it had some kind of bank switching and I found no detailed datasheet.
> 
> But then I found the same chip soldered on my card (but with 6ns) on a defective
> Maxtor 20GB HD, works fine.
> 
> Thank you for this nice DVB card improvement!
> Great work!
> But how did you do it, testing all the traces on the AV7111 with a special
> firmware that switches SCS2 in special manner?

Basically I replaced the Dpram code with a small test routine which just
writes to the SCS2 memory area in an endless loop. Then I searched for
the signal using an oscilloscope...

Unfortunately I missed the signal during the first test session.
So I took the long way around the chip... ;-)

Oliver