SX-Key Problems, First-time user

xtricity

Hi, I'm unable to load programs to the SX-Key. Any advice would be appreciated. I'm using Windows 2000 and have both a serial cable and a USB cable with the Parallax USB to RS232 converter.

After failing to upload the program, I tried to communicate with the SX-Key using HyperTerminal. I've set HyperTerminal to

57,600
8 Bits
No parity
1 stop bit
No flow control

With no SX-Key connected to the USB or serial cable, I get no echo on the screen.

When SX-Key is connected, but no power, I get no echo in HyperTerminal.

When the SX-Key is connected and powered, I get echo in HyperTerminal.

When I type "SX-Key" (no quotes) into HyperTerminal, I get no response back.

My understanding is that I'm supposed to get a response of SX-Key???

Let me know if there's anything else I can do to test this.

PJMonty

xtricity,

It's not clear what you're trying to do. You say you're trying to, "load programs to the SX-Key." The SX-Key is designed to load and debug programs into an SX chip. There is no way to load a program into the key itself.

You need to build or buy a circuit using an SX chip, write code in the free IDE, and then download/debug the code using the SX key. Here's the Parallax page with all the basic products they sell, including the ultra cheap $10 proto boards that come with SX chips already soldered and ready to go.

Thanks,
PeterM

PJAllen

Incredibly inexpensive, yes, but not "cheap."

mediaprefect

I am no expert, but:
1) goto http://www.parallax.com/sx/downloads.asp and download the SXKey software and install it. While you are there, download the documentation and read through it, at least the intro chapters. It does not sound like you have an understanding of how the programmer (SX Key or Blitz) is used.

2) If you are still having trouble communicating with the Key/Blitz, there is (http://forums.parallax.com/forums/default.aspx?f=7&m=65604&g=66110#m66110) a program "SX Key Serial Tester" which can help you with a connection problem between your PC and the programmer. There is a link to it in the forum at the link shown above.

3) Re post on the forum if you are still having troubles. You do not need to use a terminal program for normal programming of the SX micros.

Good luck,

Rick B

PJMonty

PJ Allen,

Semantic point well taken.

Thanks,
PeterM

xtricity

Thanks so much for the help. Everything is working now. That SXKeySerialTester was the key. I can now load and run the programs on the SX28. The source of the problem was an incorrect wiring of my power supply. I had it going through an extra voltage regulator, which was probably dropping the voltage below 5VDC. When I took out the extra regulator, it started to work. Well, I guess I should have simply tested the input voltages with a mmeter.

BTW, as a tip to other people trying to figure out if their SX-Key is working properly, a powered key will interface with a serial line terminal emulator. I just confirmed this with my now working SX-Key. (thanks to people here for that.) Typing "SX-Key" in HyperTerminal will return SX-Key??? (with ??? being some odd characters). Though, a better test seems to be this SXKeySerialTester since it clearly says, "found" or "not found." Just makes things a bit more definite. Oh, and putting a multi-meter on the input power leads might be helpfu.