ssd1681: Fix OverflowError for displays larger than 255x255. #90
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Need to explicitly truncate to just the low-order byte; otherwise, creating these bytearrays results in `OverflowError: value must fit in 1 byte(s)`.
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Also: if I have the time I'll see if this pattern occurs in other drivers too and add fixes for them as well. |
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When trying to use this driver with a display with dimensions larger than 255x255, the arithmetic operations that attempt to format the width and height into a pair of bytes in the ssd1681 driver's
power_upfunction leaves extra overflowing high-order bits in the low-order byte, resulting in an error:OverflowError: value must fit in 1 byte(s), originating from line 146 (for widths larger than 255) or 153 (for heights larger than 255).This PR fixes this by explicitly masking out just the low byte; it also fixes another instance of this pattern in
set_ram_address(though I've not gone into detail trying to figure out inputs to actually trigger an error from this instance).I've tested this change using an 400x300 HINK-E042A88 SSD1683 display, connected via an Adafruit eInk Feather Friend to my Adafruit Feather RP2040.
Based on my tests I can confirm that this PR addresses the above issue; display operations appear to run correctly with it.