[Coco] 4 Port MPI PCB artwork (so far)

RETRO Innovations go4retro at go4retro.com
Sat Mar 7 01:55:37 EST 2015


Here is a link to what I think is a finished 4 port design:

http://s6.postimg.org/v09zrn6yp/PCB1_3.png

  * All lines routed
  * 3 power source options (5V coax, 5V Mini USB, 5,12,-12V PSU)
  * Minimal IC count
  * Uses 2 IDE cables (40 or 80 pin work equally well)
  * On board 3V3 voltage regulator
  * All ports have smoothing caps
  * 4 position selector switch
  * 4 selection LEDs
  * Buffer board is 3" long, and main PCB is 5.75" long.

Some notes/questions:

  * The size will not allow a cartridge to be pulled out by grasping the
    top and bottom of the cart.  The minimal part-to-port distance
    requires inserting and removing carts by grasping at the sides. 
    Thoughts?  Should I increase the distance to the amount on MPI?
  * T ensure nothing interferes with the carts, I had to move the
    smoothing caps under the board.  Not a huge deal, but they will
    protrude 12.5mm (1/2 inch).  I know some folks were looking for a
    low profile unit.  Is 1/2" too high?
  * The LEDS would not fit in between the slots, unless i increase the
    interslot distance.  They are now positioned immediately below the
    switch.  Thoughts?  If I increase the slot distance, I could put
    them back in front of the cart, but you would not be able to see
    them if you have the unit mounted behind the Coco with the slots
    parallel to the back of the Coco.
  * Should the switch be behind the LEDs, or in front?
  * One of the designs had an cart autostart disable.  Is that of interest?
  * Another design had a reset disable.  Thoughts?

Jim



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