Yesterday, I decided to resolder the connections on my VFD since they weren't all that good when I got the LCD (it was done by someone else). I left all the wires in their place and just heated them up and added some solder, that was all what was necessary, since there was very few solder. Ok, so everything looked nice and clean. I went to my pc to hook it up, but nothing happened. But I've noticed that LPT1 has the address 3BC or something like that and LCDStudio wouldn't accept that, so I changed the address to LPT3 (I'm using a PCI card and I can change all my port addresses). When I did that there suddenly were 3 characters on my VFD, but nothing more happened. Then I had to reboot because I had changed the address. During the boot the 3 chars remained on the VFD and all of a sudden 2 more lighted up, so I had 5 weird characters on my VFD. Nothing happened when I started LCDStudio, so I unplugged the parallel port connector, but still, the 5 characters remained. Then I unplugged the molex connector and after that I plugged everything back in. But still nothing happened. The 5 chars were gone and nothing came back on. The weird thing is that the 5 chars stayed on the display during boot and that they didn't go away when I unplugged the parallel port connector. What could this be? How do I solve it?
If I disconnect my parallel port display while it's on, everything that was on the display remains there, which is why it did that. Have you tried your parallel port with something else to see if it's not damaged? (e.g. a printer) Maybe soldering it while the lead was still plugged into the parallel port did something to damage the card? Though that is unlikely.
I haven't tested it with a printer yet. Isn't there any command or program that could test the parallel port? I've found one for DOS and it's says the port is not working, but the program doesn't work correctly, because I tested it on a pc with a working port and it also said that the parallel port was broken. As for the soldering, I don't solder to live wires .
Check the port settings, is it ecp, epp, or standard... it should be ecp... The reason the characters stayed on is that the VFD has a memory that tells it what characters to keep lit/off. Disconnecting the parallel port only removes the path for new commands to get to the VFD, and so the memory stays intact as long as there is power... My guess on the 2 characters during startup is that it did the printer check that parallel ports do on boot, and sent something the VFD saw as a command to put stuff on the screen. I would check the port settings to see if you have ECP, SPP, or EPP, and set it for ECP. BTW/ what is the model/make of the VFD?
It's a Noritake one, 2*20 VFD. I bought it a year ago but until now I didn't have any serial/parallel ports on my pc. Hm, EPC? I'll see if I can change it. I think I selected Bi-directional and something else. Don't move I'm going to check (Ok, that might take I while, since I'm sure I'll start doing other stuff on my PC as well) This is the PCI card I'm using: http://vscom.de/produkte/463.html
Ok, I emailed VSCom, here's the mail: Code: Hi Anthony, no it doesn’t allow. It is always SPP. We have some other products that allow that (H-Series). Best Regards Damian -----Original Message----- From: Anthony VH Sent: Wednesday, June 25, 2003 6:59 PM To: [email]damian.gruszka@VisionSystems.de[/email] Subject: Re: Detect parallel port Hi Damian, Thank you for the program. I have one more question though. Does the card allow to switch between ECP, SPP, or EPP? And if so, where can I change it? Thanks, Anthony Should I go back to the store where I bought the card and exchange it for the slightly (+- 15€) H version of the card (I got the L version)? Or is there a way to make the VFD work in SPP mode? I'm pretty sure they won't make a problem out of it if I want to change the card, friendly people in the store .
Ok, I went and got myself a better (and more expensive ) version of the PCI card, it's got loads of options for the serial connections and the parallel conection can be changed to BiDirectional, SPP, ECP or EPP. I changed it to ECP. There's something called "Fast Received" and it's on by default, should I leave it on? I desoldered all the connections on my VFD and soldered a nice 7*2 pinheader row back in. Then I soldered all the wires to the parallel port connector and I'm pretty sure they are all correct since I soldered them wrong first, so I had to do them all again . I tried every parallel port setting, tried both LCDStudio & LCDSmartie, but in the end all this stuff didn't help, my VFD is still not giving any signal of life (and I know 100% it's not broken)!! Has anyone got any more tips?
I dont know if you tried this: Have you tested each pin for continuity? ie- used a Ohm meter to see if there are any shorts between pins? During you soldering, there could have been some solder that bridged between 2 pins. Just make sure there is no shorts between neigboring pins.
