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    The format of the system configuration table is as follows:
 
    Byte(s)            Contents
    ═══════            ══════════════════════════════════════════════
    00H-01H            length of table in bytes
    02H                system model (see following Note)
    03H                system submodel (see following Note)
    04H                BIOS revision level
    05H                configuration flags
                       Bit(s)  Significance (if set)
                       ══════  ══════════════════════════════════════
                       7       DMA channel 3 used
                       6       slave 8259 present (cascaded IRQ2)
                       5       real-time clock available
                       4       keyboard intercept
                               (Int 15H Function 4FH) available
                       3       Wait for External Event is available
                       2       extended BIOS data area allocated
                       1       Micro Channel implemented
                       0       reserved
    06H-09H            reserved
 
    The system model and type bytes are assigned as follows:
 
    Machine                   Model Byte            Submodel Byte
    ═══════                   ══════════            ═════════════
    PC                        FFH
    PC/XT                     FEH
    PC/XT                     FBH                   00H or 01H
    PCjr                      FDH
    PC/AT                     FCH                   00H or 01H
    PC/XT-286                 FCH                   02H
    PC Convertible            F9H
    PS/2 Model 30             FAH                   00H
    PS/2 Model 50             FCH                   04H
    PS/2 Model 60             FCH                   05H
    PS/2 Model 80             F8H                   00H or 01H
                                    -♦-