Re: Simple memory card player idea
Kat has put this very well. I am not very software orientated so I bow to her knowledge of how to make Linux do lots of useful things. Reading out video from a flash card without a filing system should be very easy indeed.
One approach is to store the data as literal waveforms, complete with blanking and sync. Then the readout mechanism is little more than a counter. This is wasteful of memory space so just storing active video means that you have to generate sync and blanking in the CPLD or FPGA. I say CPLD because this is well within range of a CPLD such as the Coolrunner series. An inexpensive DAC and you've got a video output.
There is the question of the filter after the DAC. Without oversampling the filter gets very hairy if you want a nice frequency and phase response. It's entirely possible to do oversampling in a FPGA. I've done it to a very high standard though that needs a lot of logic, mainly multipliers, to make the FIR. More modest arrangements can give very good results though multipliers are still needed which means FPGA rather than CPLD.
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