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Question

logging data to serial port at boot

Apr 15, 2017 7:43AM PDT

I have a small Dell Optiplex atom (no real hard drive -- just a 1GB SSD) that runs Windows XP embedded. I want to use it for a POS application but it doesn't open the cash drawer like a normal PC. The POS application sends an ascii char '7' to the serial port and this opens the cash drawer for the current PC, but all I hear is a click when the Dell Optiplex sends the character '7'.

I know there's an electrical charge involved in the drawer opening, so I though perhaps the power supply is not strong enough. BUT -- when I boot the PC the cash drawer opens. So during boot the PC must be sending something to the serial port that is enough for it to open.

My question is -- how can I figure out what is being sent to the serial port at boot up so I can modify the POS application to send the same thing? (i tried boot logging but this doesn't tell me anything). Thanks in advance.

Discussion is locked

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Answer
I'm no pro
Apr 15, 2017 8:59AM PDT

But have you opened the Start Up menu and un-checked that POS App or whatever it's called ?

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serial port
Apr 15, 2017 10:54AM PDT

I think you misunderstood me - the fact that the boot up process opens the cash drawer at startup time is not the problem -- it demonstrates that this little PC is capable of opening the cash drawer. It also demonstrates that the cash drawer has no problem of its own.

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Answer
I wrote such software years ago.
Apr 15, 2017 9:23AM PDT

When it failed like that we would take the unit back in and fix it. Sometimes it was an old solenoid and sometime something else. These were not fixed in the field so go back to your suppler and their service.

Post was last edited on April 15, 2017 9:23 AM PDT

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re: i wrote such software years ago
Apr 15, 2017 10:56AM PDT

I assume you're saying take the cash drawer back and fix it? But the cash drawer works fine when we you a normal PC. The normal PC is old, though, and noisy, and we want to use this little "embedded windows xp" machine. So I believe the cash drawer is fine.

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Ahh
Apr 15, 2017 11:03AM PDT

Then the app's author needs to tell you if their app runs on that OS.

Small world too. Our company dabbled in Embedded XP and you have to build the OS to include serial I/O and test your apps on it. Embedded XP is nothing like regular XP so you have to get the POS app author to check it out and maybe issue a special build for you.

This stuff is sadly beyond most folk. That is I went to the Embedded Windows seminars and classes so I know a little more than folk that play with Windows.

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Not to leave you completely without a fix.
Apr 15, 2017 11:10AM PDT

How about a small dual serial port Arduino that takes in that non-working serial command and spits another working open command?

Remember we don't have access to the app so we can't fix that. And since it's Embedded XP we can't apply our usual other tricks so this one is going to be a machine in the middle fix.

I don't know your skill level so I'll stop with how I could fix it.
1. Machine in the middle with an Arduino dual serial port board.
2. Install full up XP or another OS.

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Not to leave you completely without a fix
Apr 15, 2017 7:40PM PDT

Dear R. Proffitt,
Very kind of you to take the time to assist me with my problem, and I appreciate your suggestions. You're absolutely right that most people know nothing about "embedded Win XP" -- I'm really surprised that there were actual seminars on it and that you attended them!
The part I didn't really mention is that "I" am the author of the POS. It's not a very sophisticated POS, but it does record sales and it does open the cash drawer when running on regular XP. I only have to send ascii "7" to the serial port and the cash drawer opens. But, as mentioned, the "embedded XP" PC will NOT open the cash drawer and that is the PC we want to use. So, are you saying the OS might not have been built to include serial I/O? The OS sends "something" to the serial port at start-up time because the cash drawer opens during boot -- but I'm not sure what it is sending. Must be something more than just an ascii "7". But ascii "7" is what the manufacturer of the cash drawer ("Logic Controls") says will open the drawer.
Anyways, I think I've taken too much of your time already. I'm pretty much resigned to just buying a different PC --- it's not really a big deal. Just a puzzling problem!
Thanks again for your suggestions. I'm not familiar with Arduino dual serial port boards, but I'll look into it.

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I wonder.
Apr 16, 2017 9:16AM PDT

If the app opens the port at the beginning and leaves it open for the duration. Anyhow, change that to opposite of what it is now. Try in the drawer open routine to setup the comms (speed, etc) and then open, delay a split second and then send. You might have to send it twice (I've seen that.)

Embedded XP is built with a dev kit so have the OS builder go over if the serial support package is working. Also, set the com port to be old school as in 0x3f8 and irq 4.

Sorry but this is ancient lore today. While I know a bit about all this, not many do.

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This is confusing to me
Apr 15, 2017 8:06PM PDT
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This is confusing to me
Apr 16, 2017 4:58AM PDT

Yes, it is a little confusing. I'm sorry I posted my question about my serial port -- it's not really relevant or helpful to most people. I appreciate everyone's help on this but time to move on! Thank you.

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Just because this Noob
Apr 16, 2017 5:47AM PDT

Can't answer your question, there are Pro's that do a drive by and CAN Help YOU so hang in there . If you need to rephrase your question or say it differently, Start A New Thread and do a reboot Wink

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Hey! Would these work .
Apr 16, 2017 6:15AM PDT