Melles Griot / Laser Power RS232 protocol?

[telmnstr]

Daniel -
Main power LED once interlock obligations are met. Then upon pressing laser on the left laser emission LED flashses. After a short period (TEC come up I'd imagine) the led goes steady. After a short bit a 2nd red LED next to the first (and under laser emission heading) comes on. The system fault LED never comes on.

Internally the LD TEC and XTAL TEC LEDs come on immediately when hitting start, then they're joined by a 3rd LED in the back (at the same time the 2nd one on the front comes on.) I'm pretty sure the back diode / 2nd front represent the diode DC power.

Being SUPER CAUTIOUS I've used a digital camera and (aimed away from me) white card to try to inspect for any IR that the camera might pick up coming from the head but nothing.

I actually have two systems in the same state.

The hardware is just sexy.

[danielbriggs]

Re:RS-232...
The manual states pins 4 and 6 should be connected together on the serial port.
I don't remember having to do this on my units, it worked with the factory software with a simple null cable.

On the 15 pin connector, you've shorted 3 to 11... interlock. The laser should boot once start is pressed (as you've described).
If you still can't get serial communication working, how about trying manually coaxing light out?
Pin 1 is TTL input. It must be low when the PSU boots otherwise modulation is disabled. When high, it will apply the set current.
Pin 13 is signal GND.

[142laser]

I don't think these really ever had RS232 and will not work under the MG software. I believe they were programmed with an eprom programmer that Fred at One Stop laser Shop in Clearwater still has. Your best hope if they don't lase would be to send them to Fred for evaluation if he is willing. He does not usually work on the blue laser cavities himself as they are tricky but has an expert friend to do this at a cost...not cheap. Good luck! Phil

[telmnstr]

Re:RS-232...
The manual states pins 4 and 6 should be connected together on the serial port.
I don't remember having to do this on my units, it worked with the factory software with a simple null cable.

On the 15 pin connector, you've shorted 3 to 11... interlock. The laser should boot once start is pressed (as you've described).
If you still can't get serial communication working, how about trying manually coaxing light out?
Pin 1 is TTL input. It must be low when the PSU boots otherwise modulation is disabled. When high, it will apply the set current.
Pin 13 is signal GND.

I can try to enable modulation.

I'm curious what the diode voltage should be when fully running, although I'd guess modulation would be more of a current limiting thing. I can try to run it through my meter for a short bit -- meter says 20A @ 15 minutes max, that's under the 18A value.

[telmnstr]

I don't think these really ever had RS232 and will not work under the MG software. I believe they were programmed with an eprom programmer that Fred at One Stop laser Shop in Clearwater still has. Your best hope if they don't lase would be to send them to Fred for evaluation if he is willing. He does not usually work on the blue laser cavities himself as they are tricky but has an expert friend to do this at a cost...not cheap. Good luck! Phil

Ah cool, in my case they're both green so slightly less complicated.

I wouldn't be surprised if the RS232 port functionality wasn't implemented yet. Although, I didn't see an eprom in the unit -- it looks like it was some Altera FPGA or GALs or something, I'll have to take another look. I would imagine it might use a serial EEPROM but who knows.

[telmnstr]

Okay, I'm back to looking at these.

I picked up some DB-15 connectors at the hamfest, and ... ran into a guy there selling random stuff that actually has a LPC DPSS system as part of his light show hardware (spectra physics white light ion, kryptons, argons, CVs and more. Very random! I sent him here.)

With pin 3 tied to 11, the interlock is met and units come up. I've been here before, unit had an interlock loopback on it before. With pin 15 GND tied to pin 1 (modulate) during power on this should put it into modulation mode. I wait until the single emission LED comes on on PSU #1, or both on #2 (they're slightly different.) Upon supplying 5vdc to pin 1... nothing happens.

I guess I should try measuring diode current with my DMM. It's gonna be on the edge of the meters capabilities but there is a good chance the system is not working so worth a fuse.

[telmnstr]

Okay, was easy enough to hook up DMM in-between PCB and the quick disconnect lead going to the head connector on the back.

After power on the current starts to ramp up, I cut it off at 9 amps and it was still climbing. My jumper lead was getting hot and didn't want to damage anything.

So head is pulling current which is a good sign I suppose. I don't think there is red emitting from business end (Took pics with digital camera not eyeball.)

These bastards remain a mystery.