Pro-lite TL-1 LED sign protocol

[Tobin Fricke]

I recently acquired a moving-message LED sign at a garage sale. It has a
male DB-9 connector that I hope/assume is a serial port by which I can
program the sign. The question is, what is the protocol?

I made a null-modem cable (two female DB9 connectors, with pins 2<-->3,
3<-->2, 1<-->1, and 5<-->5 connected). From a terminal emulator, it seems
that any character I send to the sign is echoed back, no matter what
serial parameters I choose. This leads me to suspect that this port is
not actually an RS-232 serial port. (?) Any ideas?

The sign bears a plaque indicating "Pro-Lite Model TL-1" and also "Model
No. PL-2100W." It appears to be manufactured by U-Sun Electric Co., Ltd.
There is a ROM on board ("P/N A090128") and a Z80 CPU. There is also a
~30 conductor cardedge connector labelled "LOADER INPUT." Maybe
something could be done with that --- I don't have the original
keypad/programmer.

When powered up, the sign displays the message "* STOP MODE *".

thanks,
Tobin

 

[Tim Shoppa]

I recently acquired a moving-message LED sign at a garage sale. It has a
male DB-9 connector that I hope/assume is a serial port by which I can
program the sign. The question is, what is the protocol?

I made a null-modem cable (two female DB9 connectors, with pins 2<-->3,
3<-->2, 1<-->1, and 5<-->5 connected). From a terminal emulator, it seems
that any character I send to the sign is echoed back, no matter what
serial parameters I choose. This leads me to suspect that this port is
not actually an RS-232 serial port. (?) Any ideas?

Not all DE-9 serial connections follow what's used on the back of a PC.
If the box and your PC disagreed about which line was ground then it's quite
likely you get the results that you see.

The sign bears a plaque indicating "Pro-Lite Model TL-1" and also "Model
No. PL-2100W." It appears to be manufactured by U-Sun Electric Co., Ltd.
There is a ROM on board ("P/N A090128") and a Z80 CPU.

If you can follow the connections from the 9-pin connector to
any RS-232 receivers/transmitters to a UART you may do better. It could also
be RS-422 or even just TTL. (I've seen sign units that used a DE-9
connector to receive 7-bit ASCII parallel data + a strobe !)

Tim.

 

[Tobin Fricke]

Not all DE-9 serial connections follow what's used on the back of a PC.
If the box and your PC disagreed about which line was ground then it's quite
likely you get the results that you see.

Why is that? (crosstalk?)

If you can follow the connections from the 9-pin connector to
any RS-232 receivers/transmitters to a UART you may do better. It could also
be RS-422 or even just TTL. (I've seen sign units that used a DE-9
connector to receive 7-bit ASCII parallel data + a strobe !)

Hmmm. There is nothing obviously UART-like. The traces from the DB9 seem
to head towards a 74LS374 chip (making the "TTL" theory seem a little more
likely), or possibly the Z80 CPU. I'll try to dig up a DMM to check for
sure. There is also a 26-pin DIP labelled "8650" and "V61C16P 15" which is
rather far from the DB9 connector.

Tobin

 

[mike]

I recently acquired a moving-message LED sign at a garage sale. It has
a male DB-9 connector that I hope/assume is a serial port by which I can
program the sign. The question is, what is the protocol?

I made a null-modem cable (two female DB9 connectors, with pins 2<-->3,
3<-->2, 1<-->1, and 5<-->5 connected). From a terminal emulator, it
seems that any character I send to the sign is echoed back, no matter
what serial parameters I choose. This leads me to suspect that this
port is not actually an RS-232 serial port. (?) Any ideas?

The sign bears a plaque indicating "Pro-Lite Model TL-1" and also "Model
No. PL-2100W." It appears to be manufactured by U-Sun Electric Co.,
Ltd. There is a ROM on board ("P/N A090128") and a Z80 CPU. There is
also a ~30 conductor cardedge connector labelled "LOADER INPUT." Maybe
something could be done with that --- I don't have the original
keypad/programmer.

When powered up, the sign displays the message "* STOP MODE *".

thanks,
Tobin

I modified an XT keyboard to run my Prolite.
Shift register scans the switch matrix directly.
I emailed you what I have.
mike

--
Return address is VALID.
Wanted, 12.1" LCD for Gateway Solo 5300. Samsung LT121SU-121
Wanted GPIB Card for PC.
Bunch of stuff For Sale and Wanted at the link below.
http://www.geocities.com/SiliconValley/Monitor/4710/

 

[KimMui]

Mike can you let me know what you did to your pro-lite TL-1 as well? I have
one of these and don't know how to get it to display messages. Thanks


KimMui

 

[Bobdavis321]

Pro-lite keyboard

Could you send me that information too?