Help with ASCII plasma display
 

Hello group.

I am experimenting with a old Plasma ASCII display i had laying around.

It's an Densitron PM12C40-MPU unit. 12 lines with 40 characters.

Google isn't really helpfull but i can get some sites that show this
information:
http://www.guangdongdz.com/2product/...05_891585.html

http://gallery.zapro.dk/index.php?album=Plasma_ASCII

I have a big interest in vintage electronics, displays etc - Nixie tubes
for example, so this Plasma display is way cool in my opinion :-D

I am planning to control the display with a PIC microprocessor,
emulating an old terminal, etc.

The interface of the display is obvious an 8 bits ASCII interface with
some control pins too.

I have tried all i can to get data into the display, but without luck so
far.

There is a test-pin on the display, that when pulled low, prints an
continuous ASCII table on the display (see my images)

I have made a small test PCB with some dip-switches buttons so i can
enter some values to the data port of the display, but no reaction
whatsoever.

Anyone with some idéas to what i may miss ? I have old ASCII VFD (Vacuum
Flourescent Displays) in my possession, that just require an ASCII
character on the port and enable signal, and then it just works.

On my gallery you can see the display at poweron and printing the ASCII
table.

Via reverse engineering with my multimeter and scope, i found out this
pinout:
http://www.zapro.dk/public/misc/pinout.txt

There is a 74LS373 latch where the 8 bits databus passes - i can't get
the diplay to pull pin 1 of it low, enabling the data flow in.

If you are sitting with the information i need to get this going, please
chime in.

I have sent Densitron an email asking for support, but i'm pretty sure
they won't have the information i need anymore.

Regards,

Per, Denmark.