USB + STR9 + VB

electrogvlieghe · ‎2008-10-10

Posted on October 10, 2008 at 10:34

USB + STR9 + VB

electrogvlieghe · ‎2011-05-17

Posted on May 17, 2011 at 09:56

Hello,

I develop an application with the STR9-Comstick. The idea is to control the I/O ports with a program in Visual Basic through the USB-B connector near the pins of I/O ports.

Which dll use for that for the enumeration ?

The first application will be to generate a TTL signal for differents frequencies through a pin of the I/O ports. Is there a way to program it in C (TTL signal) for the STR9 ? And so the program in VB ?

Thanks

dhoyen · ‎2011-05-17

Posted on May 17, 2011 at 09:56

Hi,

Ok, Sorry for the misunderstanding...

To be right with you, i never played with USB, including PC side or embedded side. I can't help you for this subject. Seems not the easiest task, it's sure...

For the choose of an externel ADC, you have certainly a good reason, else, the STR912 embedded ADC could be interesting, according to the fact, it's possible to use a timer to clock it, and also a DMA to transfer data, with 0% or less than 1% CPU load.

In my project, i m able to sample at 1MS / sec. (only 1 channel;-( ), for 16Ksample, using a 32Kram buffer, and with a excellent time accuracy. If the bandwith of the USB 2.0 is 480Mbps (really optimistic, but should be realist for 50 Mbps), you could sample at this frequency without time limit ;)

Damien

dhoyen · ‎2011-05-17

Posted on May 17, 2011 at 09:56

Hi,

because i know nothing about VB with Windows, i will not reply to these question about USB and DLL.

BUT :

To program a ARM processor, in VB, it's clearly a bad idea

(no support, no ST library, no open source project, low resource and i think: simply: no compiler is available for this target).

Anyway: Do it in C.

For your project, use a STR9 hardware timer (i have a stick, only 10 pin are available outside, i hope it's possible to root 1 timer signal output (PWM))

Don't do it in software, he will not work (especially when you will try to increase the frequency)

Best way, if it's your 1st project, take a look and set your 1st project from working example. After, just change what you need.

You can use as environment for the STR912 :

Yagarto / Open OCD to program it via the embedded JTAG controller inside the STR912. Both are Opensource and legally available, and run under Windows.

Regards.

Damien

electrogvlieghe · ‎2011-05-17

Posted on May 17, 2011 at 09:56

Hello,

Thanks for your answer. i don't want to program ARM processor in VB but control the code in the ARM processor by VB.

My final project is to program a sequence acquisition for an extern ADC board connect to STR9-Comstick (via I/O ports). The program in VB will retrieve samples of signal via USB and so to view and analyze the signal on the computer.

My first application for generate a TTL signal for differents frequencies through a pin of the I/O ports was a training for learn the str9-comstick.

So i would program my str9-comstick in C by Hitop software for generate TTL signal and my program in VB will send instructions by USB to STR9-Comstick for change the frequency of the TTL signal.

Regards

Vlieghe Guillaume