USB FTDI Coders Cable

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pcmantinker
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USB FTDI Coders Cable

Post by pcmantinker » Mon Dec 17, 2018 10:55 pm

Does anyone have a good tutorial on how to make a coders cable with a USB FTDI adapter? The best I can find for making a coder's cable is to make one compatible with RS232: http://mc.pp.se/dc/serifc.html

Is there anything that doesn't involve using a NeoGeo Pocket link cable? I ordered an SD to Serial adapter that I'd be willing to use with an FTDI adapter.
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Re: USB FTDI Coders Cable

Post by mrneo240 » Thu Jan 03, 2019 3:18 pm

I tried and failed. But I'm not a hardware person at all
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Re: USB FTDI Coders Cable

Post by BlueCrab » Fri Jan 04, 2019 10:03 pm

The cheapest solution out there is to get one of the cheap USB->3.3v serial boards off of ebay (make sure whatever one you get has RTS/CTS pins, as well as the RX/TX ones) and to just solder it directly into the console using the test points on the motherboard (or if you're really adventurous, the pins on the back-side of the connector). It pretty much works out to just wiring it up directly -- no other components needed. Just search for "CP2102 3.3v" on ebay, and you should get plenty of listings of modules that'll work -- just make sure they either have pins for RTS and CTS, or at least solder points for them.

Doing the same with the connector off of an SD card adapter would work just as well (and wouldn't involve soldering to the console itself).
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Re: USB FTDI Coders Cable

Post by mrneo240 » Sat Jan 05, 2019 12:58 am

Is there a guide mentioning the test points?
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Re: USB FTDI Coders Cable

Post by BlueCrab » Sat Jan 05, 2019 7:59 am

http://yam.20to4.net/dreamcast/va1.html Has all of the test points on the board labeled (assuming you have a common VA1 board). You're looking for RxD, TxD, RTS, and CTS.
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Re: USB FTDI Coders Cable

Post by KingCrazy » Sun Jan 20, 2019 12:38 pm

I was actually privately asked about this a few months back (and forgot to check my PMs, oops!). I saw this and figured I might as well throw my work out there!

A couple months ago I set out to make a Coder's cable with little hardware knowledge. I didn't want to internally mod my Dreamcast, but instead make an actual cable that fit into the serial port on the back. I also wanted it to connect via USB, since I don't have a serial port on my desktop haha.

I found a few posts over on AssemblerGames that helped me figure out what to do: https://assemblergames.com/threads/drea ... ble.62275/

The biggest help was this diagram provided by megavolt85:
Image

This shows the connections between the head of the connector and the chip itself.
Likewise, the video at the start of the thread helped me as well, though I did run into one issue that I'll get to later.
https://www.youtube.com/watch?v=hjArIZzQuUk

For the chip, I picked up a FT232RL FTDI USB 3.3V 5.5V to TTL Serial Adapter Module for Arduino Mini Port off ebay for a couple dollars.
https://www.ebay.com/itm/FT232RL-FTDI-U ... 0148.m2813

The head of the connector ended up just being a mutilated HDMI cable connector -- the 10-pin half. I saw a few people on AssemblerGames doing this. Mine didn't turn out as nice, though! Haha.

The first problem I ran into was that the chip I picked up didn't have an RTS pin to connect the CTS from the header to. I was a bit torn, since the diagram just suggests merging it with GND and putting it on the GND pin, but the video suggested you needed to connect the CTS to the RTS pin. I ended up going with the diagram and everything worked out.

The other tricky part was getting the HDMI connector. I lopped off the connector from one end of the HDMI cable and started cutting it apart. The thing gave me a few difficulties, but eventually I got a really ugly, yet functional, connector.

Following that, I also needed to make sure the HDMI header fit into the serial port on the back. It took quite a bit of mutilating it to finally get it to properly fit -- primarily shaving off the edges so that it fits flatly on the little tray of connectors inside the port.

Lastly, the connector needs firm resistance pressing down on it to make a proper connection while inside the port. Awhile back I tried 3D printing a custom connection header for the Serial port. one of the failed attempts ended up making a perfect fit to fill up the empty space between my coder's cable header, and the top of the port. Some people on AssemblerGames seemed to use some sort of foam. You could probably also use a shaved down block of wood or something -- just be sure it's not leaving particles in your serial port!

If you've got everything soldered together and dcload isn't recognizing the connection, make sure that your cable is making good contact with the connectors in the port.

Here's a Google Drive folder with pictures of mine. It's not pretty, but it gets the job done! There's also a few pics that have extra notes on them to help.
https://drive.google.com/open?id=1TaNoe ... XeilfwX1UM

Hope that helps!
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Re: USB FTDI Coders Cable

Post by mrneo240 » Mon Jan 21, 2019 1:46 pm

KingCrazy wrote:
Sun Jan 20, 2019 12:38 pm
I was actually privately asked about this a few months back (and forgot to check my PMs, oops!). I saw this and figured I might as well throw my work out there!

A couple months ago I set out to make a Coder's cable with little hardware knowledge. I didn't want to internally mod my Dreamcast, but instead make an actual cable that fit into the serial port on the back. I also wanted it to connect via USB, since I don't have a serial port on my desktop haha.

I found a few posts over on AssemblerGames that helped me figure out what to do: https://assemblergames.com/threads/drea ... ble.62275/

The biggest help was this diagram provided by megavolt85:
Image

This shows the connections between the head of the connector and the chip itself.
Likewise, the video at the start of the thread helped me as well, though I did run into one issue that I'll get to later.
https://www.youtube.com/watch?v=hjArIZzQuUk

For the chip, I picked up a FT232RL FTDI USB 3.3V 5.5V to TTL Serial Adapter Module for Arduino Mini Port off ebay for a couple dollars.
https://www.ebay.com/itm/FT232RL-FTDI-U ... 0148.m2813

The head of the connector ended up just being a mutilated HDMI cable connector -- the 10-pin half. I saw a few people on AssemblerGames doing this. Mine didn't turn out as nice, though! Haha.

The first problem I ran into was that the chip I picked up didn't have an RTS pin to connect the CTS from the header to. I was a bit torn, since the diagram just suggests merging it with GND and putting it on the GND pin, but the video suggested you needed to connect the CTS to the RTS pin. I ended up going with the diagram and everything worked out.

The other tricky part was getting the HDMI connector. I lopped off the connector from one end of the HDMI cable and started cutting it apart. The thing gave me a few difficulties, but eventually I got a really ugly, yet functional, connector.

Following that, I also needed to make sure the HDMI header fit into the serial port on the back. It took quite a bit of mutilating it to finally get it to properly fit -- primarily shaving off the edges so that it fits flatly on the little tray of connectors inside the port.

Lastly, the connector needs firm resistance pressing down on it to make a proper connection while inside the port. Awhile back I tried 3D printing a custom connection header for the Serial port. one of the failed attempts ended up making a perfect fit to fill up the empty space between my coder's cable header, and the top of the port. Some people on AssemblerGames seemed to use some sort of foam. You could probably also use a shaved down block of wood or something -- just be sure it's not leaving particles in your serial port!

If you've got everything soldered together and dcload isn't recognizing the connection, make sure that your cable is making good contact with the connectors in the port.

Here's a Google Drive folder with pictures of mine. It's not pretty, but it gets the job done! There's also a few pics that have extra notes on them to help.
https://drive.google.com/open?id=1TaNoe ... XeilfwX1UM

Hope that helps!
you're my hero.
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Re: USB FTDI Coders Cable

Post by tonma » Thu Jan 24, 2019 1:30 am

KingCrazy wrote:
Sun Jan 20, 2019 12:38 pm
I was actually privately asked about this a few months back (and forgot to check my PMs, oops!). I saw this and figured I might as well throw my work out there!

A couple months ago I set out to make a Coder's cable with little hardware knowledge. I didn't want to internally mod my Dreamcast, but instead make an actual cable that fit into the serial port on the back. I also wanted it to connect via USB, since I don't have a serial port on my desktop haha.
...
Here's a Google Drive folder with pictures of mine. It's not pretty, but it gets the job done! There's also a few pics that have extra notes on them to help.
https://drive.google.com/open?id=1TaNoe ... XeilfwX1UM

Hope that helps!
Thanks a lot
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