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linux, image upload
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linux, image upload

by elsasa on Tue May 07, 2019 5:29 pm

So I'm slightly off the map - I fixed the problem while writing the original question so here is the answer:

You've got a minipov4 and want to use linux to upload the images and you don't want to use the conveter_thing.pde?

Well... the gotcha is in the bit order of the signed short integer that forms the first two bytes in the converted image file. It needs to be big-endian.
Otherwise it's just like theMiniPov4_ImageConverter.pde code says.

For reference the file format is:
2 bytes big endian signed short integer (N, number of columns) followed by one byte per pixel (8 pixel columns, N rows) where each pixel is :

byte=(red && 0xE0)+(green>>3 && 0x1C)+(blue>>6 && 0x03)

The byte order of the pixels is little endian.

The file can be uploaded using:

avrdude -cusbtiny -pm328p -s -D -Ueeprom:w:temp.bin:r

with the current (2019) version of avrdude and the system default avrdude.conf configuration.

elsasa
 
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Please be positive and constructive with your questions and comments.