T1000-E: Negative temperature values incorrectly displayed due to char signedness - #1391
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The ntc_temp2 lookup table was declared as 'char', which can be unsigned on some platforms, causing negative temperature values (-30°C to -1°C) to be incorrectly interpreted. Changed to int8_t to ensure proper signed integer handling of negative temperatures. Fixes meshcore-dev#1389 Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
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…#1391) Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Nit: both arrays are never modified, so const would be appropriate.
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| static char ntc_temp2[136] = { | ||
| static int8_t ntc_temp2[136] = { |
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Nit: these are never modified.
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| static int8_t ntc_temp2[136] = { | |
| static const int8_t ntc_temp2[136] = { |
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@liamcottle one-liner, good fix, good to merge! |
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Summary
ntc_temp2array type fromchartoint8_tProblem
The
ntc_temp2lookup table invariants/t1000-e/t1000e_sensors.cppwas declared aschar, which can be unsigned on some platforms (depending on compiler defaults). This caused negative temperature values (from -30°C to -1°C) to be incorrectly interpreted as large positive values.Solution
Changed the array declaration from:
to:
This ensures the array is always treated as signed, allowing proper handling of negative temperatures.
Impact
Test plan
Fixes #1389
🤖 Generated with Claude Code