Communication and/or networking between PC and Genesis?

For hardware talk only (please avoid ROM dumper stuff)
Mask of Destiny
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Post by Mask of Destiny » Wed Jan 16, 2013 8:32 pm

1. The voltages are wrong, so you'll need a level shifter like the MAX232.
2. While both gamepad ports and RS-232 serial ports use a DB-9 connector, the pinouts aren't the same so in addition to adjusting the voltage you'll need to wire the connector differently.

So you can use one of those, but creating the adapter from RS-232 to Genesis serial isn't really any easier than getting an FTDI breakout board or Teensy and wiring one up to an appropriate connector.

Many of those adapters probably use an FTDI internally and I believe at least some of the FTDI chips have a configurable output voltage, so I suppose you might be able to hack an existing adapter to produce the correct voltage. I don't think it's worth the effort though.

Chilly Willy
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Post by Chilly Willy » Wed Jan 16, 2013 10:35 pm

There are serial to USB cables/adapters that work with 5V/GND signal levels, so you don't need level shifters for those cables. The MAIN reason not to use serial<>USB is IT'S TOO DAMN SLOW!! As mentioned several times, the max baud rate for serial on the Genesis is 4800 baud. That's roughly 8 bytes per frame you can send/receive. You might be able to use that for certain applications with very low bandwidth for communications.

djcouchycouch
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Post by djcouchycouch » Thu Jan 17, 2013 5:03 pm

Chilly Willy wrote:USB is IT'S TOO DAMN SLOW!! As mentioned several times, the max baud rate for serial on the Genesis is 4800 baud.
Ah, I see. Are there any alternatives?

TmEE co.(TM)
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Post by TmEE co.(TM) » Thu Jan 17, 2013 5:09 pm

LPT port and the awesome cable by Mask of Destiny :P
Mida sa loed ? Nagunii aru ei saa ;)
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen

Chilly Willy
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Post by Chilly Willy » Thu Jan 17, 2013 5:38 pm

djcouchycouch wrote:
Chilly Willy wrote:USB is IT'S TOO DAMN SLOW!! As mentioned several times, the max baud rate for serial on the Genesis is 4800 baud.
Ah, I see. Are there any alternatives?
Yes - they're listed in the first two pages of the thread... hint, hint. :wink:

GManiac
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Post by GManiac » Thu Jan 17, 2013 5:52 pm

He-he, I worked with link cable by KRIKzz some years ago (generally he made its first version for my needs, I believe) and got transfer speed of 85 KB/s on it. Later versions with SD card interface are much faster.

djcouchycouch
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Post by djcouchycouch » Thu Jan 17, 2013 6:00 pm

Chilly Willy wrote:
djcouchycouch wrote:
Chilly Willy wrote:USB is IT'S TOO DAMN SLOW!! As mentioned several times, the max baud rate for serial on the Genesis is 4800 baud.
Ah, I see. Are there any alternatives?
Yes - they're listed in the first two pages of the thread... hint, hint. :wink:
Ah yes. Brain not firing on all four cylinders.

Actually, I'm confused (nothing new there!). There's a difference between serial and the controller port? They're not one and the same?

Mask of Destiny
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Post by Mask of Destiny » Thu Jan 17, 2013 6:22 pm

djcouchycouch wrote: Actually, I'm confused (nothing new there!). There's a difference between serial and the controller port? They're not one and the same?
The controller port supports both serial and parallel I/O. The difference is how you configure the port on the Genesis side and what kind of hardware you're using to interface it to your PC on the other side.

MintyTheCat
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Post by MintyTheCat » Thu Jan 17, 2013 7:05 pm

TmEE co.(TM) wrote:LPT port and the awesome cable by Mask of Destiny :P
Using a Parallel Port was once a great, easy Option (lots of fun Interfacing as a Kid) and it was easy to debug as it required no specialised Timing through Clocks. However, finding a Motherboard with a 'proper' Parallell Port is not too easy these Days. I tried to use MOD's Cable and Software myself and found Issues with my Motherboard's Levels.

Has anyone found an add-on Parallel Card that behaves like a 'real' Parallel Port?

Chilly Willy
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Post by Chilly Willy » Thu Jan 17, 2013 8:48 pm

MintyTheCat wrote:
TmEE co.(TM) wrote:LPT port and the awesome cable by Mask of Destiny :P
Using a Parallel Port was once a great, easy Option (lots of fun Interfacing as a Kid) and it was easy to debug as it required no specialised Timing through Clocks. However, finding a Motherboard with a 'proper' Parallell Port is not too easy these Days. I tried to use MOD's Cable and Software myself and found Issues with my Motherboard's Levels.

Has anyone found an add-on Parallel Card that behaves like a 'real' Parallel Port?
Linux has a way of making plug-in parallel ports work like "normal" using ioctl calls. Windows does not. Look at the code repo for ucon64 for an example of how any parallel port works with almost no effort in linux, but must be backwards compatible in Windows.

MintyTheCat
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Post by MintyTheCat » Mon Jun 03, 2013 8:17 am

Chilly Willy wrote:
MintyTheCat wrote:
TmEE co.(TM) wrote:LPT port and the awesome cable by Mask of Destiny :P
Using a Parallel Port was once a great, easy Option (lots of fun Interfacing as a Kid) and it was easy to debug as it required no specialised Timing through Clocks. However, finding a Motherboard with a 'proper' Parallell Port is not too easy these Days. I tried to use MOD's Cable and Software myself and found Issues with my Motherboard's Levels.

Has anyone found an add-on Parallel Card that behaves like a 'real' Parallel Port?
Linux has a way of making plug-in parallel ports work like "normal" using ioctl calls. Windows does not. Look at the code repo for ucon64 for an example of how any parallel port works with almost no effort in linux, but must be backwards compatible in Windows.
Cheers! I am about to put together another Linux Machine and I'll be testing the Parallel Port. It is a simple way of doing things and I hope it works. Thanks.

Chilly Willy
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Post by Chilly Willy » Mon Jun 03, 2013 5:53 pm

Just ask if you run into any trouble. Remember that after configuring the project, you need to edit the config.h file and change the PPDEV flag like this:

Code: Select all

/* use ppdev for parallel port I/O (default: no) */
#define USE_PPDEV 1

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