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I am trying to design a device that captures DV (digital video) from camcorder and stores it on sd card. The camcorder produces ~4MB/s of data which the device needs to capture and save to SD card.

What should I take into consideration when picking right microcontroller for this task? How to calculate max speed of IO using controller data sheet? How does running input and output at the same time affect bandwidth?

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  • \$\begingroup\$ Which interface must be uaed to connect to camera? \$\endgroup\$
    – Justme
    May 27, 2021 at 20:14
  • \$\begingroup\$ It has DV output with firewire connector which I believe uses pretty simple serial protocol \$\endgroup\$ May 27, 2021 at 20:18
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    \$\begingroup\$ As well as speed you will have to consider latency, which, in turn, will determine the minimum buffer memory required. \$\endgroup\$ May 27, 2021 at 20:18
  • \$\begingroup\$ You buy these for about $15 , can you make it better? Cheaper? Faster than FireWire? \$\endgroup\$ May 27, 2021 at 20:19
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    \$\begingroup\$ Why do you think DV over FireWire is simple? You must find a chip to interface it. I don't think any MCUs have FireWire interface built-in, it's also been declared dead by Apple in 2008. \$\endgroup\$
    – Justme
    May 27, 2021 at 20:27

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FireWire pretty much rules out anything on the market that's usually considered a microcontroller. Also, FireWire is certainly not what I'd call a "simple serial protocol".

4 MB/s and SD card as writing target is yet another indication that you need a device with sufficient RAM for buffering; so, again, not a microcontroller.

I don't think FireWire is common anymore in SoCs integrating a sufficiently powerful application processors, so quite likely you'll either want a device that has PCIe and is able to run a mainstream operating system (Linux?) that has support for a commercially available PCIe/FireWire bridge (if such a thing still exists), or you'll want an FPGA SoC and someone with extensive digital design experience to implement a FireWire controller in the FPGA. It might still be, by far, easier to let a normal operating system running handle the SD card, filesystem and buffering.

So, sorry, not a microcontroller's job, it seems.

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