Here's[1] a useful piece of hardware that I found. I had a somewhat difficult time finding one, so I just wanted to share it with everyone. It's an adapter that allows the use of a dip8 chip in place of a soic8 surface mount chip.
[1]http://www.epboard.com/eproducts/protoadapter3.htm
wt
On Fri, 19 Jun 2009 00:18:03 -0700, Warren Turkal wt@penguintechs.org wrote:
Here's[1] a useful piece of hardware that I found. I had a somewhat difficult time finding one, so I just wanted to share it with everyone. It's an adapter that allows the use of a dip8 chip in place of a soic8 surface mount chip.
Thanks. ePBoard Design makes some great adapters :-)
I have ben eyeing this one for a while: http://www.epboard.com/eproducts/parts/EPL-0032.htm
They also make some really cool DIP8 to flash memory adapters. http://www.epboard.com/eproducts/parts/EMC-0015.htm
Hmm that has got me thinking, could flash memory be used to replace SPI?
On 19.06.2009 13:54, Joseph Smith wrote:
They also make some really cool DIP8 to flash memory adapters. http://www.epboard.com/eproducts/parts/EMC-0015.htm
Hmm that has got me thinking, could flash memory be used to replace SPI?
Similar protocol for some variants, but a totally different command set. In short, unusable for onboard firmware.
Regards, Carl-Daniel
On Fri, Jun 19, 2009 at 15:02, Carl-Daniel Hailfingerc-d.hailfinger.devel.2006@gmx.net wrote:
On 19.06.2009 13:54, Joseph Smith wrote:
They also make some really cool DIP8 to flash memory adapters. http://www.epboard.com/eproducts/parts/EMC-0015.htm
Hmm that has got me thinking, could flash memory be used to replace SPI?
Similar protocol for some variants, but a totally different command set. In short, unusable for onboard firmware.
All one would really need is some fast µC (enough fast to keep up with mb SPI and convert the command set) with two SPI interfaces to convert SD/MMC to motherboard SPI. That would be really cool btw, if it would work :)
Urja Rannikko wrote:
All one would really need is some fast µC (enough fast to keep up with mb SPI and convert the command set) with two SPI interfaces to convert SD/MMC to motherboard SPI. That would be really cool btw, if it would work :)
Basically, it won't.
The protocol used on the mainboard has pretty strict timing for response from the flash chip, no microcontroller will be able to keep up. It is even doubtful if a state machine in programmable logic would be able to respond quickly enough.
Note that only MMC (the very old cards) use 1-bit SPI. Any newer card uses a wider interface, which means even more complex translation logic.
And even if the translation state machine would be fast enough, if e.g. it runs off it's own clock at maybe 100MHz instead of whatever is on SPI, the consumer grade flash memory cards can themselves have longer response times than what is allowed by the mainboard SPI.
MMC has unlimited response times, as an example. Ie. the card can take as long as it wants to respond, at least for writes.
The cards can also have rather complex voltage requirements.
All in all, a ton of work, and even doubtful that it could succeed.
//Peter
On Sat, Jun 20, 2009 at 02:32, Peter Stugepeter@stuge.se wrote:
Note that only MMC (the very old cards) use 1-bit SPI. Any newer card uses a wider interface, which means even more complex translation logic.
Although it doesnt matter, every SD card must support 1-bit SPI (by spec).
And even if the translation state machine would be fast enough, if e.g. it runs off it's own clock at maybe 100MHz instead of whatever is on SPI, the consumer grade flash memory cards can themselves have longer response times than what is allowed by the mainboard SPI.
MMC has unlimited response times, as an example. Ie. the card can take as long as it wants to respond, at least for writes.
The cards can also have rather complex voltage requirements.
Complex = 3.3V? (depends on the card though)
All in all, a ton of work, and even doubtful that it could succeed.
I tought of this for a while (after i sent that message) and, we'll i doubt its not even possible directly, it would need an ASIC with some serious caching to work, if possible.
Honestly, I was thinking of getting the adapter I linked to and getting the reverse adapter and soldering the exact serial flash chip that is currently on my motherboard onto the reverse adapter. Then I could have a few of those. Because that have the exact same chip, I'd hope that I could just plug it in and expect it to work.
wt
On Fri, Jun 19, 2009 at 5:37 PM, Urja Rannikkourjaman@gmail.com wrote:
On Sat, Jun 20, 2009 at 02:32, Peter Stugepeter@stuge.se wrote:
Note that only MMC (the very old cards) use 1-bit SPI. Any newer card uses a wider interface, which means even more complex translation logic.
Although it doesnt matter, every SD card must support 1-bit SPI (by spec).
And even if the translation state machine would be fast enough, if e.g. it runs off it's own clock at maybe 100MHz instead of whatever is on SPI, the consumer grade flash memory cards can themselves have longer response times than what is allowed by the mainboard SPI.
MMC has unlimited response times, as an example. Ie. the card can take as long as it wants to respond, at least for writes.
The cards can also have rather complex voltage requirements.
Complex = 3.3V? (depends on the card though)
All in all, a ton of work, and even doubtful that it could succeed.
I tought of this for a while (after i sent that message) and, we'll i doubt its not even possible directly, it would need an ASIC with some serious caching to work, if possible.
-- urjaman
-- coreboot mailing list: coreboot@coreboot.org http://www.coreboot.org/mailman/listinfo/coreboot
Warren Turkal wrote:
Honestly, I was thinking of getting the adapter I linked to and getting the reverse adapter and soldering the exact serial flash chip that is currently on my motherboard onto the reverse adapter. Then I could have a few of those. Because that have the exact same chip, I'd hope that I could just plug it in and expect it to work.
Yep, that would work just fine.
//Peter
On Sat, Jun 20, 2009 at 5:53 AM, Peter Stugepeter@stuge.se wrote:
Yep, that would work just fine.
KISS rule wins again. :)
wt
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Carl-Daniel Hailfinger -
Joseph Smith -
Peter Stuge -
Urja Rannikko -
Warren Turkal