Displaying Letters Using 7-Segment Displays      This information is taken from "Blast from the Future" in  DATAFILE V22N5p13 by Jordi HidalgoA few calculators with 7-segment displays can display letters.  Thecalculators and their BCD digit assignments are:modelABCDEFreference21ArHoPEblankDATAFILE V21N2p42The 21A was the first to have letters for messages.  You could spell "Error".25ArFoPEblank65N V4N6p16a,33A""""""PPCJ V6N1p17d,34C""""""PPC CalculatorJournal V7N6P29c67ArCodEblank65 Notes V4N1p6b97A""""""and V4N4p4a97A(printing).-+*blankC/R65 Notes V4N4p6b12Cr-oPEblankDATAFILE V20N5p2715Cr-oP/uEblankPPC CalculatorJournal V10N1p52d