Silicon Chip ECG

On Sat, 9 Dec 2006 22:49:16 +1030, "aldo" put finger to keyboard and composed:

Yes, although the software has one or two quirks. What's the problem?

- Franc Zabkar

There is no display on the graph. The red led flashes then the green led flashes a few times, then nothing.

On Sun, 10 Dec 2006 10:18:04 +1030, "aldo" put finger to keyboard and composed:

The software misbehaves until such time as an ECGSAMPL.cfg file is created, after which it works flawlessly. If this file is subsequently deleted (or renamed), the software plays up again. In my case the reason this file was not being created was because I was closing the application by clicking on the "X" in the top RH corner of the program window instead of selecting File -> Exit.

I suggest that you configure your settings, then select File->Exit to save your ECGSAMPL.cfg file. Then re-launch your program and all should be well. I'm not certain, but you may also need to set the VCP's flow control to None.

- Franc Zabkar

That means that you have, in fact, died.

geoff

Thanks, will try what you suggested. Also the other day in desperation I reprogrammed the pic chip in case that was the issue. Do you know what option need to be set when programming in regards to wachdog timer on/off power up timer on/off and what oscillator mode should it be set to. Thanks

It's working fine after I tried what.you suggested. I was not closing the app by file/exit. I programmed the pic with watchdog timer off, powerup timer on, and HS oscillator mode and seems to work ok.

I just bought one but haven't put it together yet. Are you sure it only does a few seconds? Isn't that a software issue ?

I'm going to be really p****d off if it does.

My understanding of it was a continuous monitoring of heart beat and I need it for exactly that because I get irregular beats a couple of times during the day and need to have it connected for quite some time(hours) as one does not know when it's going to happen.

Any comment Frank?

Regards Paul.

On Thu, 14 Dec 2006 15:41:30 +1030, "Boozo" put finger to keyboard and composed:

Return it. You're going to be p****d off. The device stops after collecting 8192 samples. That could be 4 seconds or 16 secs worth, depending on the sample rate.

AFAIK Silicon Chip have decided not to release the VB source code, nor the PIC source. This is unfortunate because a continuous monitoring feature is mandatory IMO. At the very least one should be able to record several minutes of readings even if they cannot be processed and graphed in real time. Perhaps if all three of us wrote a letter to Leo Simpson ...

- Franc Zabkar

On Thu, 14 Dec 2006 09:28:05 +1030, "Aldo" put finger to keyboard and composed:

I wrote to Silicon Chip about this problem in November of last year. It took me a long time to find the solution but it appears that SC didn't bother to pass the info on. Perhaps you could write to Leo Simpson ...

- Franc Zabkar

What's the interface? Perhaps it wouldn't be too hard to reverse engineer...

I would be interested in having a look. I dont mind reverse engineering and VB is piss easy to reverse!. PIC is not so easy.

Oh, ok. I actually meant if it's a parallel port interface, it wouldn't be too hard to whack a logic analyser on it and record some operations so you could work out what data is being sent and received, so you could write a completely new program to drive it. I.e. reverse engineer the interface, not the software.

The kit uses a USB to SERIAL module from Elexol.

Oh, cool, even easier. Just need an RS232 T circuit that feeds each end's transmissions into separate RS232 input lines (e.g. two wired RS232 ports), and a simple program to log the RS232 traffic.

I don't have one of the ECG units, as you can tell, but it doesn't seem like it'd be hard to work out :-).

Thedre is no PIC source but hex file is about 35 lines long - that should be easy to disassemble

Tom

I just did a similar job. Why wont SC release the source code?

Because they are not really interested in educating their readers, but more lining the pockets of their kit supplier mates.

The projects are trivial toys but the source code is treated like the be all and end all of some magnificent highly engineered device.

Oh for the good ol days of the ETI 660 and Dream computers when these magazine types were overflowing with source code.

I sent an unacknowledged letter to Leo Simpson many years ago bemoaning the "security" device embedded into one of their $10 projects, a temperature sensor from memory. For Christs sake, a toy but you were expected to pay royalties to some author for some software that was probably lifted from the application notes.

Ray

On Fri, 15 Dec 2006 10:00:58 +1100, Clifford Heath put finger to keyboard and composed:

The PIC I/O is RS232 (Tx/Rx/CTS/RTS), but it communicates with the PC via a serial-USB converter module internal to the ECG device. VB6 talks to the device via a virtual COM port driver.

Here is the relevant software:

VB program:

Windows drivers for FTDI's FT8U100AX, FT8U232AM and FT8U245AM USB controller:

PIC hex file:

I suspect that the following utility may be able to eavesdrop on the virtual COM port.

Portmon for Windows v3.02:

- Franc Zabkar

I just installed the app, no wonder they dont release source code. Once can usually judge the quality of the code behind the application simply by looking at the design itself. The app is absoloute rubbish. They couldn't even change the installer directory from the default "Project 1" name. The icon is the default MS VB icon..

Looking at the native code looks like the had the brains to change the naming of the objects to something usefull though. The application is quite small, so it should be easy to reverse..