[sane-devel] Plustek OpticPro A320E (07b3:1826): third version published - no attachment this time

[Tero Kankaanperä]

Hello list,

On the subject of Plustek OpticPro A320E backend...

THIRD VERSION IS PUBLISHED

   https://terokankaanpera.fi/a320e/

Since the published 2026-08-28 version:

   - x scale corrected: 0.75 % long before, 0.9991 +- 0.0001 now, measured
     with a ruler at 200, 400 and 800 dpi
   - the whole bed is scannable, 304.8 x 431.8 mm, and the black tail 
and the
     comb of stripes at the right-hand edge are gone
   - the lamp now goes out when the carriage starts back, +0.22 s after the
     last image byte (CommandSetGl124::save_power is empty upstream)
   - the motor acceleration curve is the vendor's measured table rather than
     the constant-acceleration model, reproducing the vendor entry for entry
     at five of six resolutions
   - FWDSTEP/BWDSTEP are written per phase and FSTPSEL is no longer tied to
     STEPSEL, both as the vendor does

One of these changes what a user must do: the white calibration target now
has to be at least 305 mm wide, because this scanner has no internal white
strip and A3 paper is 8 mm too narrow. The README says so up front.

Patch: 17 files, +3394 / -28, against master fcaa30a7.

Everything that would have made this message long is in changes.md at the
same URL: the version-by-version account, what was measured, and the four
places where I found a difference against the vendor and deliberately did
not copy it.



-- 
---
Tero Kankaanperä
https://terokankaanpera.fi