[Coco] Driect Connect Modem pack to Drive pak conversion.
sales at gimechip.com
Tue Nov 2 00:44:26 EDT 2010
Replacing the Crystal may require that the 6551 be replaced with a 6551A,
which is a good idea anyway since the 6551A is rated at the 2Mhz bus speed.
Of course if it works without replacing it, then I guess the "if it ain't
broke don't fix it" applies :)
Or did the DCM Pak have a 6551A? My deluxe RS-232 has the 6551...
----- Original Message -----
From: "Mark Ormond" <markormond at mtxsystems.com>
To: "CoCoList for Color Computer Enthusiasts" <coco at maltedmedia.com>
Sent: Monday, November 01, 2010 11:28 PM
Subject: [Coco] Driect Connect Modem pack to Drive pak conversion.
>I scored a Direct Connect Modem Pak off ebay with a joystick and Orchestra
>90-cc pak for cheap.
> I really don't need a modem, so I decided to try to make it into a drive
> To do the basic conversion you will need.
> 1 28 Pin socket.
> 1 udrive
> 1 microsd card.
> 1 27128 thru 27512 (your choice) eprom with coconet. If using a larger
> rom, just repeat the image till the rom is filled.
> Cut the rom from the modem pack and install the 28 pin socket.
> Run a jumper wire from pin 2 of ic3 (74ls133) to pin 26 of the rom
> (This enables A13 on the socket, thus giving us 16k eprom capability)
> Go ahead and install your eprom and make sure coconet comes up.
> Now turn over the board and solder a jumper wire between pins 16 and 17 of
> the 6551 uart (IC2)
> Next up, cut out the modem chip located at IC5 (74HC943n) (Yes this chip
> is a 300 baud modem)
> Now from the empty socket The pins you will need are as follows.
> Pin 5 RXD
> Pin 6 VCC (+5)
> Pin 11 TXD
> Pin 14 GND
> Socket Udrive
> 5 4
> 6 5
> 11 3
> 14 2
> Please double check and triple check your connections here.
>>From the Udrive check for continuity to the following.
> Udrive card edge pins
> 2 33
> 5 9
> Udrive 6551 Uart (IC2)
> 3 10
> 4 12
> Now throw in your microsd card that you have written the distribution
> image to using Cocopak and turn on the coco.
> Right now it's running at 115200, I'll swap the crystal when I have a
> I don't have reset for the udrive hooked up at the moment either.
> I've also rigged up the connect switch as a halt switch and
> I'm going to use the mode switch for hi low eprom bank select (a14).
> The card just fits thru the modem phone jack hole, and the udrive is held
> in place with double sided foam tape. (From Radio Shack of course)
> Thank you for all your hard work Roger.
> Please support Roger and his work. Without it, this hack wouldn't have
> been possible.
> Coco mailing list
> Coco at maltedmedia.com
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