Never used the MAX7219 so correct me if I'm wrong but reading the datasheet it looks like for each digit on the display you need to shift out 16bits. 4 digits x 16bits = 64bits.
If the SPI clock is 100kHz then shifting out those 64bits takes 6.4us meaning the the absolute best you will ever get (not taking ANY processing into account) is 1500 updates per second while you want it to display 10000 different values in 0.2 seconds (50000 updates per second).
Also, and perhaps I've misunderstood this but, you do realise that the display is multplexed right?
If you're trying to film it actually displaying all values between 0 and 9999 in 200ms then I don't think that's going to happen, no matter how fast you shift out the data.
The datasheet specifies the scanrate to be 800Hz meaning the display refreshes 800 times per second with all 8 digits being used. During your 200ms "window" the display readraws itself 160 times and you expect it to able to show 10000 different values during that time?
Granted, with only 4 digits and using the scan-limit register you can make it update the display faster but even if it scans a 4 digit display 1600 times per second you're not even CLOSE to being able to "show" 10000 unique values in 200ms.
/Henrik.
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