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FWIW, a couple of them are now supported by Arduino, by adding them through the boards manager.

By clk, you mean one of the GPIO signals generated by the DMA? You could run the DMA in regular mode instead of circular. and then only use a data array which produces 8 clk cycles. But if you only want to stop one signal while the othes continue, it becomes more tricky.

​@@simonmartin_ch the code is running perfectly. thanks to you. but I want to stop both the output and the clk pin to stop after 8 pulses. I only want 8-bit outputs at pulses(1 bit = 1 pulse). but I am unable to stop the clk and output. although I try regular DMA. still not working. Any suggestion.

Did you find a way to do this, I need to stop the DMA, change the data buffer en then start the dma again. So as to enable a sort of binary data sending functionality via a pin that gets toggled. However I can't stop the dma at the right points. There is a dma abort function but that takes up too much time to execute..?

@@markusmulder8040Correct, stopping the DMA is inefficient. Use regular DMA configuration in the CubeMX interface. Then start the DMA exactly the same way. HAL_DMA_Start(&hdma, my_data, &destination, lenght);

@@simonmartin_ch I HAVE TRIED EVERYTHING. also change the DMA. but it still does not show a signal on two pins.

@@simonmartin_ch is there any possibility of HAL library error.

@@exaltedcodiing6655 Excellent observation. But you *did* configure the DMA to increment the source adress? If you did, maybe the HAL library has a bug right there...

I do not think you can combine addresses like that. You need to think about how the DMA controller works in the background. Which is essentially moving data from one address to another address. I would be very surprised if the DMA could write to 2 addresses (2 GPIO ports) at the same time. If you need so many high-speed parallel signals you might really hit the limits of an MCU and consider an FPGA. However, maybe you can use 2 seperate DMA channels (triggered on the same timer) to achieve what you want. But when you do this, make sure, that the DMA channels do not block each other by using the same bus. There are tables in the datasheet of the MCU which describe the DMA channels (which can be active at the same time) because the BUS fabric architecture is dependent on which MCU you use. And if that works there might still be a chance that both GPIO ports have a slight difference in timing, perhaps non-static so that you have jitter between the signals of both ports. I would try this and then measure the output signals. I hope this helps.

@@simonmartin_ch Thank you Simon for your kind guidance, I DO appreciate your time and effort. I use F103C8T6 running at 72Mhz my update event Clock is 1Mhz so 500khz Frequency and the smallest pulse I make is around 5us = 5 update events, I get very low jitter with this config. which is very important for me. In fact, I have just enough GPIO pins in port B for this task( around 14 I need), however, I'm a bit conservative about future updates on software, so I may add a few more another reason for using two ports was that unfortunately all the pins of a specific port are not placed all side-by-side in an LQFP48 package so they come out of every corner of the MCU and contaminate my sensitive Analog sections and ADC reads, (haven't tested it yet, so it may or may not). At the end of the day, if using two ports with DMA would cause more jitter and instability, I would most probably go with one port solution for now and work on my Embedded skills to find a better solution in the future maybe.

hm.. i need to check my drive to see if I still have this thing somewhere

@@simonmartin_ch ok tell me when u find it cause it luks rly cool and i wanna try it

@@mackenziewilson1420 it is back online! (Firefox was laggy here so I recommend Chrome) simonmartin.ch/drumpads

Mikes930 I got mine online from a Chinese seller on ebay/aliexpress. Sparkfun has a USB host shield too.