jvz@sdcsvax.UUCP (John Van Zandt) (10/18/84)
Does anyone have any experience controlling I/O directly from UCSD Pascal on an IBM-PC? I want to manipulate an AST board from a Pascal program, but cannot figure out what statement(s) to use. The normal trick of using a pointer to map to the memory/io space only works on micros with a memory-mapped i/o structure. Are there any special functions available? Or does anyone know how to write functions in assembly language which are compatible with Pascal function calls? John Van Zandt UCSD ucbvax!sdcsvax!jvz
ee173xcj@sdcc3.UUCP (David Johnson) (11/03/84)
> Does anyone have any experience controlling I/O directly from > UCSD Pascal on an IBM-PC? I want to manipulate an AST board > from a Pascal program, but cannot figure out what statement(s) > to use. The normal trick of using a pointer to map to the memory/io > space only works on micros with a memory-mapped i/o structure. Are > there any special functions available? Or does anyone know > how to write functions in assembly language which are compatible > with Pascal function calls? > > John Van Zandt > UCSD > > ucbvax!sdcsvax!jvz There are several ways to do this in UCSD-Pascal on the P_system. First, there might be a function in the IBMSPECIAL unit, but I am not sure (I don't have it here in the VAX lab). Secondly, using Processes (V IV.13) one can access interupt vectors, but I don't know if this would do it, after all I don't even know what an AST board is! Thirdly, one can write functions and procedures in assembly language. One must use the SYSTEM.ASSMBLER and then LINK the result to a unit or program. To do this, one has to declare a routine as external. Look in your manual, or if you don't have one, drop by the EE/CS 61 lab. David Johnson UCSD