Some time ago I was developing a medical instrument which required histogramming, which got me in the mood to retake my own PIC MCA project(http://home.comcast.net/~prutchi/index_files/scint.htm ). I used the variable RAM in the microcontroller (16F877), so I limited the number of channels to 95 and let the histogram run until some channel reaches 240 counts (the highest 8-bit number that yields an integer when divided by 8 which is also divisible by the 30 pixel height of the LCD). The firmware then displays the spectrum as a bar with a maximum height of 30 pixels for each one of the 95 channels.
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Click here for a pdf of the schematic diagram for the front-end of the MCA
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Hi,
Is 240 really the largest 8-bit number divisible by 8? I would think it’s 248.
– David
Thank you David!
I should have further qualified that statement to incorporate the 30 pixel height of the display. I have modified the portion in parenthesis to “the highest 8-bit number that yields an integer when divided by 8 which is also divisible by the 30 pixel height of the LCD.”
Cheers,
David