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Chapter 2. Data Structure
2. Data Structure MR350MKII system control data structures are outlined in the following diagram.
The system kernel uses the File Allocation Table (FAT), File Handle Table (FHT),
Communication Control Table, Device Control Table and Key Alias Table. The
following sections will describe each one of these control tables. The description
includes a "typedef" part and the "default" values of the table.
Terminal Application EXEC
Kernel
2.1. Device Control Table
The device control table contains MR350MKII peripheral configuration information
including the barcode scanner port, the badge reader port, LCD display, keyboard
and buzzer output. The barcode scanner is controlled by a separate data structure
and barcode control table, to be discussed later.
2.2. Type Definition
typedef struct { BYTE scanner;
BYTE badge;
BYTE lcd_backlight;
BYTE buzzer;
BYTE keylock;
BYTE buzzer_volume;
} DEV_CONFIG;
scanner: 'N' = enable scanner port
'F' = disable scanner port (default)
badge 'B' = enable badge port for barcode slot reader (default)
Terminal Control Table Device control table
File Allocation Table File Handle Table Comm Control Table
RS232&RS454