Chapter 3. System Kernel; Application Programming Interface; Keypad Subsystem - Unitech MR350 MKII Technical Reference Manual

Chapter 3. System Kernel

3. System Kernel
3.1.

Application Programming Interface

The MR350MKII kernel includes three basic modules: device driver, file manager
and DOS manager. The programmer can design the application programs by calling
those available functions just as in the PC DOS environment.
The ROM based operating system of the terminal provides emulated MS/DOS
function calls. The calling and parameter passing conventions are identical to that of
MS/DOS. A detailed description of the functions supported by the Terminal's
subsystems, I/O interface, DOS manager and File manager are listed in appendixes A
and B.
The software to be run on the MR350MKII may be programmed by using 16bits
Microsoft C/C++ or Borland C/C++, and the IBM PC macro assembler version 1.0
and later versions.
computer or stored in a file.
? ?
NOTE when using Microsoft C/C++ :
When program execution area is assigned less than 64K (see section 4.3) and a
program of more than 64K is run, a run time error message, "Not enough space for
environment", will be shown. In this case add following statements in main:
and link with: >LINK /NOE mypgm
3.2.

Keypad Subsystem

The keypad subsystem scans the key matrix, converts the scan code to its associated
key value, and stores the value in the keyboard input buffer for program utilization.
Note that the [SHIFT] key is not stored in the buffer, it is used to distinguish the
alphabetic and numeric mode of associated key positions and provide an alternative
key code. The following table shows the key values of each key.
Transaction data can be processed interactively with the
/* mypgm.c */
_setenvp()
{
}
main()
{...
...
...
}
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