The BBC and Master Computer Public Domain Library

ABB3 ASC

Submitted by Steve Fewell

Description:

Call the Evaluate value routine (&AD36) which will evaluate the next value at BASIC text
pointer B location, or the expression at that location if the value begins with an open bracket ("(").
If the obtained value is not a String (A is not 0) then generate a Type mismatch error as a string is required.

If the length of the String (&36, the length of the SWA) is 0 then set the IWA
to -1 and exit, as a zero length string does not have a valid ASCII code!.

Otherwise, Load A with the ASCII code of the first character and jump to routine &AE18 to set the IWA to the
8-bit value of A and exit.

Disassembly for the ASC routine