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BBC Micro Elite

Text: DTW1 (6502SP version)

Name: DTW1 [View in context] Type: Variable Category: Text Summary: A mask for applying the lower case part of Sentence Case to extended text tokens
This variable is used to change characters to lower case as part of applying Sentence Case to extended text tokens. It has two values: * %00100000 = apply lower case to the second letter of a word onwards * %00000000 = do not change case to lower case The default value is %00100000 (apply lower case). The flag is set to %00100000 (apply lower case) by jump token 2, {sentence case}, which calls routine MT2 to change the value of DTW1. The flag is set to %00000000 (do not change case to lower case) by jump token 1, {all caps}, which calls routine MT1 to change the value of DTW1. The letter to print is OR'd with DTW1 in DETOK2, which lower-cases the letter by setting bit 5 (if DTW1 is %00100000). However, this OR is only done if bit 7 of DTW2 is clear, i.e. we are printing a word, so this doesn't affect the first letter of the word, which remains capitalised.
.DTW1 EQUB %00100000