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High Speed GPIO

boxhed

HI there

 

 

I'm looking for an easy to use, high speed GPIO PIC dev board like the DM164142

 

 

However I see the clock is 1 MHz, internal. I need GPIO frequencies of less than 1 micro seconds. Can this board be modified to increase this? Or is there another board with a faster clock with available GPIO

 

Any feedback is more than welcome

 

Kind Regards

Lew.

  • in reply to boxhed

    You might find these a better bet:

     

    https://www.microchip.com/design-centers/8-bit/pic-mcus/device-selection/pic18f-q10-product-family

     

    Twice the speed but still an 8 bit PIC, cheapo dev board available.

     

    Good luck.

     

    MK

  • Hi Guys

     

    Firstly thanks very for your replies, they are much appreciated and apologies for not providing more information

     

    I an electronic engineer, who used to develop with PICS, but tbh its been 10 years and I've lost most of  what I learned and probably the nerve

     

    I wanted to use the PIC as I was somewhat familiar. And didn't want to buy tools, and the kit I suggested has online tools and easy programming by the looks of it. The reason I picked that PIC cos it has loads of GPIO.

     

    I was unsure about the programming of the Clock away from 1 MHz  as I was afraid that the Dev Kit wouldn't program once I did that. However Ill be honest I didn't know it had a 32 MHz internal clock and would require an external one.

     

    a 1 MHz GPIO toggle will probably do the job to be honest

     

    The Application is a high speed pulse generator to switch a high speed solid state relay

     

    Thanks for your help guys

     

    Lew

  • Hi Lewis,

     

    I don't know where you're getting this information from. You can go to the datasheet for the chip used on that dev board (PIC16F18877) and see that it supports 32 MHz clock speed). GPIO rate will be partially dependent on the code you're using.

    Just about any microcontroller will allow GPIO to be toggled higher than 1 MHz.

    As for the easy-to-use requirement, don't all dev boards aim to assist in this, by making it easy to use the device? It's not really possible to suggest any better because no-one knows your experience or purpose for requiring this 1 MHz GPIO rate.

  • First off, you haven't read the data sheet quite right, on page 109:

     

    The internal clock modes, LFINTOSC, HFINTOSC (set

    at 1 MHz), or HFINTOSC (set at 32 MHz) can be set

    through the RSTOSC bits

     

    You mention "GPIO frequencies of less than 1 microseconds", by which I assume you mean GPIO toggle rates in excess of 1MHz.

    The PIC16F18857 has an instruction rate of 8MHz, so it will struggle to do any more than crank one pin up and down at 1MHz. If you want to do any other processing at that speed then this is not the right chip.

     

    I find that almost all of the questions I respond to on E14 require a great deal more information than the question poser provides - and yours is not an exception to this rule.

     

    How about explaining a bit more ?

     

    I can't make a guess at which processor might be better for you unless you first tell me:

     

    What you actually want the processor to do.

    Why you started with this PIC.

    Do you prefer, want or have to use a PIC.

    What can you do (ie what experience have you got) - no point me suggesting a solution that is out of your comfort zone.

     

    Diagrams often help.

     

    MK