Genesis Rear DB-9 Connector

[blackevilweredragon]

This is not a completed project, but it's almost done..  It's aim, is to make my Genesis support things like the MegaModem, and the special arcade machine that used a Genesis (which required the DB-9 connector in the back)...

For those that are unfamiliar, Genesis model 1's had a rear Female DB-9 connector.  Later Genesis 1's did NOT have this connector, so didn't the Genesis 2.

However, if one takes apart the Genesis 1 without the DB-9 connector in the back, you will notice it has the solder pads, but missing components.

My mod, is to make that port work again, and add those missing components...

This is before:  http://blackevilweredragon.spymac.com/genesisdb.jpg

And this is where I am currently in the mod:  http://blackevilweredragon.spymac.com/db9mod.jpg

As of right now, I have only currently identified the "Ferrite Bead"..  But I can't I dentify what goes in the "EMx" pads..  The controller port has the component, but I can't figure them out either, they have no markings except the numbers "222"..

[NFG]

Those are just filters as far as I know, they clean the signal but do little else.

For the record, that ferrite bead of yours is/should be a COIL, that's what the little curly symbol is.  

I think.  ^_^

[blackevilweredragon]

Those are just filters as far as I know, they clean the signal but do little else.

For the record, that ferrite bead of yours is/should be a COIL, that's what the little curly symbol is.  

I think.  ^_^

if it's supposed to be a coil, or inductor, then why does it have the "FB" labling?

If I just connected them all with ferrite beads (and leave the center pin----ground untouched), will it work fine?  i want to do this with the simplest components i can possibly get..

[NFG]

If it's NOT a coil why is it marked differently than the other EM filters?  HUH?  Answer me THAT!?

You could probably just short all the other lines, skipping the center leg which (IIRC) is just GND.

Great pics, BTW.

[blackevilweredragon]

If it's NOT a coil why is it marked differently than the other EM filters?  HUH?  Answer me THAT!?

You could probably just short all the other lines, skipping the center leg which (IIRC) is just GND.

Great pics, BTW.

The controller ports look to have ferrite beads too, with the same swiggly lines

i'll just short the rest with ferrite beads (better than nothing)..

thanks, i use the Macro mode on my camera, all the time, when taking pictures of circuits..

[blackevilweredragon]

All done (i shorted the rest with regular wire----insulated)

http://blackevilweredragon.spymac.com/db9rear.jpg

[Dr.Wily]

Which feature provided by this port ? (whitout magamodem)

[blackevilweredragon]

there was an arcade machine, that used this port..  it allowed it to control the console, like, select which game you wanted to play, and start it..

[kendrick]

There was also a Japan-only modem that connected here, wasn't there? You could get serial port functions off that connector (but it didn't match a PC serial pinout, as I recall.)

-KKC

[blackevilweredragon]

technically, the rear port is like the front controller ports....

i think RS232 functions were emulated.  cause, when i dump my game carts into ROM files, i dump them via controller port TWO on my Genesis..

[RobIvy64]

I remember when I first got a model 1 Genesis in ~1998, I thought the EXT port was a CGA video port B) . All I knew was PCs at that time