int e l 1.5 WHAT'S THE DIFFERENCE BETWEEN V1.0 AND V1.1 ADDITIONS TO MCS BASIC-52 V1.1: A number of new assembly language user OP BYTES have been added. These permit the user to make better use of the STATEMENT/COMMAND expansion option previously described. Details of these new OP BYTES are presented in Chapter 9.6 of this manual. The length of the input buffer has been increased from 72 characters to 79 characters and the ERROR: LINE TOO LONG has been eliminated. Instead, when the cursor reaches the 79th position a bell character will be echoed every time the user attempts to enter another character. A new variation on the PRINT (including PH0. and PH1.) and LIST statements have been added.
This new option is evoked with an @ character (EXAMPLE: PRINT@ or LIST@ and permits the user to write specific output drivers for these statements and commands. When the @ PRINT or LIST is evoked, MCS BASIC-52 CALLS external code memory location 403CH. The user must put the specific output driver in this location. More details of this option is in Description of Statements section of this manual. The control stack has been made more "forgiving." This means that the user can execute a GOSUB to a subroutine that contains a FOR-NEXT loop and return from the subroutine without completing the FOR-NEXT loop. Version 1.0 would yield a C-STACK ERROR under these circumstances, V 1.1 yields no error.
The question mark character ? is interpreted as a PRINT statement (EXAMPLE: (PRINT 10+20 is the same as ? 10+20). The symbols P. remains a shorthand notation for PRINT just as in V1.0. The FOR-NEXT statement can be executed in the direct mode. This lets the user write short routines in the DIRECT MODE to, for example, display a region of memory (EXAMPLE: FOR I = 200H to 210H: PH0. XBY(I): NEXT I) Variables can be up to 8 characters in length, however, only the first character, the last character, and the total number of characters are of significance. This lets the user better describe variables that are used in a program.
Chapter 1.4 details the limitations on the expanded variables in Version 1.1 . - 11 -