The apparent wire on the rear Escom boards.
The pre-Escom boards have no wire.
Salvaged boards awaiting repair.
Three different board revisions and three
Different ways of dealing with the mouse port.
An obvious after thought on earlier board.
A more elegant solution. By the time the
The size of the clock-port header
Simple home brew mod to allow the fitting
Minimum you need to see if a board is working.
The earlier 1B boards with the surface wires.
Without this wire to the VideoDAC the earlier
The earlier boards mounted the mouse port
The Budgie appears to have been the subject
That rather clumsy looking Budgie
No rogue wire on pre-Escom boards.
Different case badge to Escom machines.
Rev 1D.4 boards used on my Escom 1200s.
Chips on the Escom board date 1992/93.
With the exception of the ROM chips the
My Escom boards are Rev 1D.4 with the
Small green LED to escom drives.
Modified Panasonic PC drives used.
The apparent wire on the rear Escom boards.
The pre-Escom boards have no wire.
What I posted previously on Escom
March 18th 1801: scuzzblog: Amiga and Escom - The Right Price or just a Noble gesture.
ScuzzBlog: Diaries December 2023
Entry 08th December 2023: Post 1: Amiga 1200 - Motherboard variations.
Amiga 1200 - Motherboard variations.
There was a question recently on one of the forums about a hack
discovered to the rear of an Amiga 1200 Escom motherboard. The
wire appears to have been installed to overcome the use of a
modern PC type floppy drive. Or so I believe. The issue then
comes as to how you identify an Escom motherboard... from
above. Tricky.
The A1200 came in various revisions with the most popular the
1D.4 and 2B. I do have a number of 1B boards. The main issue for
me has been the way the mouse-port was handled with either a
fixed port to the main board or via a port ribbon or detachable
small daughterboard.
Additionally the earlier boards had a small wire connecting two
pins on the VideoDAC; a long wire connecting the Budgie; and a
variety of ways the clock-port pins were dealt with. The clock-port
often involved bending over two pins or half the whole connector.
This was to enable other items such as the PowerFlyer to be
installed.
Interestingly my Amiga Technologies or Escom motherboards are of
the Rev 1D.4 version and not the later 2B. They have a simple
resistor variation to the clock-port and that previous small wire
from the Budgie. The main difference is the green LED light in
the floppy drive and the case badge with the new logo.
So seriously good luck determining from that lot which exactly
are Escom boards or otherwise. Although the fresh production of
Amiga 1200s in 1995 were assembled in France the only new chips
on the board are the 1995 3.1 ROM. Commodore never actually
released the 3.1 ROM before going bust given that the ROM was
distributed under license from Village Tronic.
Anyway this is what I said ....
This may help.
https://forum.amiga.org/index.php?topic=31946.0"
The problem of timing as I understand it really affects 040 and
060 boards of the day. Various fixes of boards were supposed to
be implemented but the 1D.4 and 2B went ahead without fixes.
Escom released the same revision boards but made their own modest
changes. The only way I can tell an Escom product is from the case
and the floppy drive.
EyeTech did revise boards further but these were mostly for the
tower upgrades.
You would have to ask a current supplier of kit which boards to
avoid.
Board Revisions:
Rev 0 (Engineering Prototype)
Rev 1 (Advanced engineering prototype)
Rev 1A (Initial Release)
Rev 1B
Rev 1D.1
Rev 1D.3 (Budgie Rev -01 Release, E123C and E125C have been removed
from motherboard)
Rev 1D.4 (Budgie Rev -02 Release, additionally XR358 470Ohm resistor
removed, 470Ohm resistor added to pin 43 of Alice)
Rev 2B (Both budgie Rev -01 and Rev-02 were used. Resistor 118 was
changed from 470Ohm to 220Ohm)
To my knowledge Escom [ Amiga Technologies ] did not release any
new board revisions.
Worth watching this ...
https://www.youtube.com/watch?v=G6fYOjTYvXM
My Escom floppy is a Panasonic JU-257A605P and has this little
green LED to the port mouth.
https://www.scuzzscink.com/amiga/scuzzblog_july22_1/car_sbd_150722_15.jpg
Further reading on the drive sent me here:
https://www.kernelcrash.com/blog/more-modding-floppy-drives/2015/08/20/
Its obviously something to do with the way Escom were able to use
modern floppy drives in their 1995 machines. Issues arise maybe if
you use an old Commodore fitted drive pre 1994. I really don't know.
That YouTuber video suggests he had another video about the floppy mod.
Amiga 1200 - Motherboard variations.
different solutions to a problem.
Budgie had been upgraded.
was always obviously too large.
of kit like the PowerFlyer.
Monitor and power plus possibly a mouse.
boards will not boot so do not remove.
port on the motherboard. Very useful to
have the detachable mouse port as its easier
to fix if one of your mouse pins snaps off.
As did happen to me once.
of various changes in its short life.
wire again. I have often wondered
what the spare chip slot is for on
the right there. If you know do drop
me a line.
chips on the Escom board date 1992/93.
highlighted modifications.
< o|o >
~ March 18th 2021 ~
If you can only see this CONTENT window
then click the image above for the full site
Last updated 9th December 2023
Chandraise Kingdom
Keep the Faith
scuzzscink 2023