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7 years, 4 months ago.
What is the operations frequency from the DISCO-F746NG ?
Hello, I make a little test program.
DigitalOut control(D2);
main() { while(1){ control = 1; control = 0; } } But the frequency is ~ 13.3 Mhz ! It is ok so, or give it a option to make it faster ? Greatings Bernd
1 Answer
7 years, 4 months ago.
If you want to know the core frequency, print SystemCoreClock (it is an integer with current clock speed). Toggling pins has some overhead. Although you can go faster, FastIO (https://developer.mbed.org/users/Sissors/code/FastIO/) is useful for that, although it does not support the F7. I expect if you use the F4 code it will work, but sometimes they randomly change register names to irritate me.
Hello Erik, At first thank you for your reply. The print commando say 216000000. That is ok. I used the Disco-Board F746 and I used the SPI Port on the Arduino Pins. The SCLK frequency is the same. I write spi,frequency(20000000). Also I used the Fast USB Port to store fast samples from my ad converter with 4000Hz. But it work not fast enough for my system. Do you can help me.? Regards Bernd
posted by 08 Dec 2016What do you do exactly with Fast USB Port? Since 4kHz ADC is not that fast. Assuming 2 bytes per sample, and you need 64kbit/s, even a regular Serial (UART) should easily handle this.
posted by 08 Dec 2016Hello Eric, sorry for delay. I read with the SPI Port (2Mhz clk) 20 Bytes from my adconverts( 5* AD1271) in a interrupt function to store it in a buffer(8192Byte). When the buffer is full I want to write it to my USB Stick.In this tiem, the next buffer whould be filled. I tested with the DIsco Board(F746NG) and it seems what is to fast. with trgger rate from 4Khz. With 1 Khz it is ok...Do you have i idea? I am not a specialist in this area. Thanks Bernd
posted by 12 Dec 2016