53 lines
1.1 KiB
Markdown
53 lines
1.1 KiB
Markdown
# scale-code
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USB ID: `1446:6a73`
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A CLI utility in Go to read weight data from a Stamps.com USB postal scale via HID.
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Originally developed to revive old electronics gifted by a family member. This project documents the quirks, bias, and calibration of the device for others interested in low-cost hardware reuse.
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---
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## Usage
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```sh
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go build -o scale-code
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sudo ./scale-code
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```
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The program continuously polls the scale and displays the weight in ounces, rounded to the nearest 0.1 oz.
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You must run it as root (`sudo`) or use a proper udev rule to grant access to `/dev/hidraw` devices.
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---
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## Calibration
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### Observed Bias:
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```
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W = Stamps.com scale
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WT = Taylor digital scale (Walmart, new)
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Test object: consistent, arbitrary small item
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W1: 1.9
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W2: 1.9
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W3: 2.0
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WT1: 2.0
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WT2: 2.0
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WT3: 2.0
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```
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### Adjustment:
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A linear correction factor of `0.952` is applied to compensate for the 0.1 oz low bias, yielding more accurate readings.
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---
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## License
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MIT License © firebadnofire 2025
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FOSS, for the preservation of still-functional hardware and the freedom to study it.
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