Installing µIEC in a SX-64

Wanting massive storage and a minimum of soldering in your good old Commodore SX-64? I just found the solution by using the UIEC 3.2 without the daughterboard (article: UIEC-SD-BA) supplied by Jim Brain / Retro Innovations!

IMG_6897.JPG

I made a little dual IEC connector to plug in between the internal drive and the controller board allowing you to add a secondaty internal IEC driver. The µIEC only emulates the IEC protocol so it’s not a real 1541 replacement and does not allow fast loader and most common trackloaders (which sends a binary to the drive’s memory and cpu) to function properly. If you need full 1541 emulation i would recommend the 1541 Ultimate 2 cartridge.

So this is what i have done to accomplish the additional drive space;

The only pin which needs to be soldered to the expansion board is pin 2 on the user port. This is the 5V feed for the protocol emulating uIEC card (see SX-64 schematic diagram)

IMG_7050.JPG

Next thing is to make a dual IEC board. This was very simple, just a 6-pin female and two 6-pin male pin headers soldered to a little PCB.

IMG_7051.JPG

IMG_7052.JPG

Now when this is done just plug it in to the header P11 of the I/O board (see page 13 of the schematics) and connect the other wires accordingly. To figure out the pin assignment for the µIEC i used the following scheme:


P11 I/O ------------------- µIEC
_________________________________
pin 1 -------- SQR -------- pin 4
pin 2 -------- GND -------- pin 1
pin 3 -------- ATN -------- pin 7
pin 4 -------- CLK -------- pin 5
pin 5 -------- DATA ------- pin 6
pin 6 -------- RESET ------ pin 3


User port ----------------- µIEC
_________________________________
pin 2 -------- 5 volt ----- pin 2

If you like you can peek here for some hints.

IMG_7054.JPG

IMG_7055.JPG

Now the internal drive, number 8, and the SD card is accessible via drive 10 (default setting of the µIEC).

As this SX-64 already been modified (to sport a Teletron 1200 modem internally) the storage bay was already altered. I decided to use double-sided sticky-tape to mount the µIEC to the right upper side of the storage bay.

IMG_6897.JPG

Everything worked out just fine even at first start up!

This entry was posted in Hardware, SX-64, µIEC and tagged , , , , , , . Bookmark the permalink.

Leave a Reply