Is my Blitz dead?

Steel

When I try to program a chip, the code compiles fine, but I get an "SX-Key not found on COMX"· (x being my assigned comport - COM4).

I have gone to device Manager, and the Blitz has taken Com4.· When I plug in the cable,· the Blitz enumerates.·

I have gone into configuration to make sure the USB Port is correct.· It is.

So the USB Functionality is all working, however when I try to program, it tells me that the Key is not found...

Is my Blitz Dead?

Shaun

·

Bean

What are you plugging the blitz into ?

Make sure you have 5.0 volts at the programming header.
Make sure the SX has the MCLR pin pulled high.
Make sure the SX chip is not defective. Try another chip.

Bean.

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Post Edited (Bean (Hitt Consulting)) : 11/10/2007 2:49:16 AM GMT

Steel

Hmmm... This is odd.· I haven't come across this before.·...

I am using the SX-Tech Board.· It is plugged into 9V.· There is 5V on VDD and 0V on VSS (at the programming port.)· The Reset is sitting high, unless the rst button is getting pushed, in which case it is pulled low.

I switched to a different chip just to make sure that the chip is not the issue.

The SX Blitz is connected (facing the right way) and plugged into my PC by USB Port.· SO hardware-wise...everything 'looks' good.

I removed/re-installed the FTDI drivers.

-The SX Blitz took COM4.· (See Devman.jpg).
-When I open up SX-Key, and go to configuration, COM4 is the available port (See Configure.jpg)
-When I open up a sample file and try to program it...It says it compiled correctly...and then pops up the error message (notfound.jpg)

*Sigh...of course this happens just before I am about to purchase my first batch of SX-48 to do some development...


When I put a scope probe on OSC1 or OSC2, there is no data.· OSC1 sits at 2V.· OSC2 sits at 3V.








Post Edited (Steel) : 11/12/2007 9:47:44 PM GMT

darco

In my use of the blitz, I've noticed some issues as well--especially if I "hot plug" the blitz.

I have found following this procedure works reliably for me:

1) Plug blitz into unpowered board.

2) Turn on the board power.

3) Connect the USB cable to the blitz.

Deviating from this procedure causes me problems.

Steel

Wow! That totally worked! Thank you, darco.

This is the first time I have come across this issue in the year and a half I have used the SX...Very odd.

Thank you for your setup procedure.

Parallax- is there a way that this can get looked into as a bug?

Shaun

darco

I run into this issue all the time, and I'm amazed more people aren't aware of it. Maybe most people are using the SX-Key. *shrugs*

I'm thinking that this issue could be caused by one (or both) of the following:

1) When connecting the blitz to an already powered-on board ("Hot-plugging"), it is possible that an oscillator pin is being connected before both of the power pins are connected, which might put the SX chip on the blitz into an bad state. (If this is indeed the problem, it could be fixed by making sure that the oscillator pins on the connector are shorter than the power pins)

2) When the blitz is only connected to the computer, some of the power from the FTDI chip might be bleeding into the SX chip, putting it into a bad state. The only solution here (aside from a hardware revision) is to make sure that you always plug the blitz into the USB port last.

After coming up with the above mentioned procedure, I haven't bothered debugging the issue further. It would be nice if it could be fixed in a future hardware revision, so as to save others the frustration.