Code 128 — Teaching Tool (A/B/C)

Main page unchanged (Fit/Manual size). Popup restored with big annotated example + clickable symbol cards.
Checksum: Start + Σ(i×code[i]), then mod 103. Non-stop symbols are 11 modules; Stop is 13.

Encoding breakdown

#RoleShownCode valuePatternChecksum weight
Checksum total (before mod 103)
Checksum (mod 103)