Page 5 of 6

Re: Serial port speed read write benchmark

Posted: Thu Feb 02, 2023 12:06 pm
by fafadou
VirtuaShenmue wrote:Thanks for the answers!

It would be cool to have dreamsheel boot directly from the dongle.


You must "say" to the console to read the serial port, it's why the only way is to have a new bios.

Re: Serial port speed read write benchmark

Posted: Thu Feb 02, 2023 3:29 pm
by VirtuaShenmue
fafadou wrote:
VirtuaShenmue wrote:Thanks for the answers!

It would be cool to have dreamsheel boot directly from the dongle.


You must "say" to the console to read the serial port, it's why the only way is to have a new bios.


I guess the community already tried, but so it isn't possible to force the startup from the serial port in some way?
The Bios during the startup, doesn't check the serial port at all?

Re: Serial port speed read write benchmark

Posted: Thu Feb 02, 2023 7:50 pm
by Ian Micheal
VirtuaShenmue wrote:
fafadou wrote:
VirtuaShenmue wrote:Thanks for the answers!

It would be cool to have dreamsheel boot directly from the dongle.


You must "say" to the console to read the serial port, it's why the only way is to have a new bios.


I guess the community already tried, but so it isn't possible to force the startup from the serial port in some way?
The Bios during the startup, doesn't check the serial port at all?

Tiny bin loaded on start up from the disk even works most times on half dead gdroms..Not like it's damaging anything..

Re: Serial port speed read write benchmark

Posted: Wed Jun 28, 2023 9:33 pm
by grenert
I'm a lurker here, and this is an old thread, but I want to add my experience to the lot. I got the "V2" serial SD card adapter (available all over ebay), and I tried 8 different SD and microSD cards, none of which were able to be recognized by either Dreamshell or Retrodream (discs running from the GD-ROM). The cards were as small as 512MB and as large as 256GB. All formatted in FAT32. I could often get acknowledgement that an SD card was connected during Dreamshell booting, but it could never read from it. Retrodream would either just hang on startup, or if it booted it would not show an SD card connected. I think these serial card adapters are just too finicky to work with most cards.

I mostly wanted this for running homebrew and emulators. I don't really want some gigantic collection of every DC game made, so ODE isn't something I'm interested in. Fortunately, I have a nice CD-RW drive and my GD-ROM still works, so will keep on truckin' with CDs...

Re: Serial port speed read write benchmark

Posted: Thu Jun 29, 2023 5:10 am
by Dirge Of Ram
Out off the eight you got, Need a Class 10 speed SD Card and make sure you full format with 64/32kb selected.

https://www.amazon.co.uk/Kingston-SDS2- ... 109&sr=8-3

Best One.

Re: Serial port speed read write benchmark

Posted: Thu Jun 29, 2023 12:17 pm
by grenert
Thanks for the suggestions. I don't have the cards in front of me to check Class 10 or not, but I found cheap Class 10 cards online (Sandisk and Transcend), so will give those a try when they arrive.

Re: Serial port speed read write benchmark

Posted: Sat Jul 29, 2023 10:56 pm
by grenert
Well, these are the cards I've tried so far (also some Sandisk MicroSD cards not shown). No luck at all. All cards formatted FAT32, 32K and 64K clusters tried. Even tried full format (not quick). I get one of three errors:
No acknowledgement that an SD card is present.
SD card cannot be read.
SD is present but MBR cannot be read.
At this point, I've concluded either there is something about my particular DC that it will not use this SD reader, or that it is so picky about SD cards I'll have to spend a hundred bucks and many hours to find a compatible one. I'm glad my optical drive is still OK, and I have a good CD burner!

Re: Serial port speed read write benchmark

Posted: Sat Jul 29, 2023 11:40 pm
by Ian Micheal
make sure the light flashes and it's connected many serial ports on dc have dust and grime and rust and when you push it in .. It never really connected..

Old cheap as walmart brand 32gb cards always work .. If the serial port is damaged due some mode someone did that is possibility.. Long as the card is proper full size sd card no micro to sd addapter thing then it will work. Dont have to spend 100's watch to see if it lights up when it tries to boot. Are you using the right version and the files are where they should be on the sd card.. Also dont use any sd card extender they dont work on this. why do all those look like they take micro sd cards those do not work..

also kingston cards works so does any proper sd card i always use under 32gb format it using a proper format program not windows..

Re: Serial port speed read write benchmark

Posted: Sun Jul 30, 2023 6:52 am
by aldair
grenert wrote:Well, these are the cards I've tried so far (also some Sandisk MicroSD cards not shown). No luck at all. All cards formatted FAT32, 32K and 64K clusters tried. Even tried full format (not quick). I get one of three errors:
No acknowledgement that an SD card is present.
SD card cannot be read.
SD is present but MBR cannot be read.
At this point, I've concluded either there is something about my particular DC that it will not use this SD reader, or that it is so picky about SD cards I'll have to spend a hundred bucks and many hours to find a compatible one. I'm glad my optical drive is still OK, and I have a good CD burner!

Need to remove the five capacitors from the serial port.

Image

Re: Serial port speed read write benchmark

Posted: Sun Jul 30, 2023 6:58 am
by MoeFoh
grenert wrote:Well, these are the cards I've tried so far (also some Sandisk MicroSD cards not shown). No luck at all. All cards formatted FAT32, 32K and 64K clusters tried. Even tried full format (not quick). I get one of three errors:
No acknowledgement that an SD card is present.
SD card cannot be read.
SD is present but MBR cannot be read.
At this point, I've concluded either there is something about my particular DC that it will not use this SD reader, or that it is so picky about SD cards I'll have to spend a hundred bucks and many hours to find a compatible one. I'm glad my optical drive is still OK, and I have a good CD burner!


If your card reader is known to be good and if the serial port on the Dreamcast has been cleaned and if there have been no mods to the Dreamcast, then this rare issue could be the problem:

serial-1.png


serial-2.png


From sd card reader designer: jj1odm