GetVect Get Protected mode interrupt handler address.

Inputs: AX = 0204h

BL= Interrupt vector number.

Outputs: CX:[E]DX = selector:offset of handler.

Errors: None.

Info Get system selectors/flags.

Inputs: AX = 0ff00h

Outputs: AX = Selector for real mode segment address of 00000h, 4G limit.

BX = Selector for current PSP segment. 100h limit.

[E]CX = DOS transfer buffer size. Always <64K.

DX = DOS transfer buffer real mode segment address.

ES:[E]SI = DOS transfer buffer address.

ESI+ECX always <64K

EDI = System flags. Bits significant if set.

0 - 32 bit code default.

1 - Virtual memory manager functional.

2 \ Mode, 0 - raw, 1 - VCPI, 2 - DPMI.

3 /

4 - DPMI available.

5 - VCPI available.

6 - No memory managers.

7 - Descriptor table type. 0 - GDT, 1 - LDT.

Errors: None

Notes: Bits 1-2 of DI indicate the interface type being used by CauseWay.

Bits 4-5 indicate the interface types that are available. Bit 7 indicates the descriptor table being used to allocate selectors to the application when on a raw/VCPI system. The DOS transfer buffer is the area CauseWay uses to transfer data between conventional and extended memory during DOS interrupts. This memory can be used as temporary work space to access real mode code as long as you remember it may be overwritten the next time you issue an INT in protected mode that requires segment pointers.

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