int e l COMMAND/STATEMENT EXTENSIONS (VERSION 1.1 ONLY) The user may also use the command/statement extension option to re-define the syntax of MCS BASIC- 52. This is done simply by placing your own syntax in the user table and placing the appropriate BASIC token in front of your re-defined keyword. A complete listing of all MCS BASIC-52 tokens and keywords are provided in the back of this chapter. MCS BASIC-52 will always list out the program using the user defined syntax, but it will still accept the standard keyword as a valid instruction.
As an example, suppose that the user would like to substitute the keyword HEXOUT for PH1., then the user would generate the following entry in the user table: EXAMPLE: ; USER_TABLE: DB 8FH ; TOKEN FOR PH1. DB 'HEXOUT' ; TO BE IN ORDER IN THE DB 00H ; USER LOOKUP TABLE ; DB 10H DB 'DISPLAY' DB 00H ; REST OF USER_TABLE ; DB 0FFH ; END OF TABLE MCS BASIC-52 will now accept the keyword HEXOUT and it will function in a manner identical to PH1. PH1 will still function correctly, however HEXOUT will be displayed when the user LIST a program. - 157 -