Commodore Amiga A500 Technical Reference Manual page 158

PC JANUS SERVICE
This service is called via INT JANUS.
AH contains a function code
J_GET_SERVICE
Gets a new Service Number
Expects:
nothing
Returns:
AL : New Service Number to use
- 1 if no service available (J_NO_SERVICE)
J_GET_BASE
Gets Segments & offset of Janus Memory
Expects:
AL : Janus Service Number
Returns:
ES : Janus Parameter Segment
Dl : Janus Parameter Offset (if defined),
else – 1
DX : Janus Buffer Segment
AL : Status (J_OK. J_NO_SERVICE)
J_ALLOC_MEM
Allocates Janus Memory
Expects:
AL : Type of memory to allocate
BX : Number of Bytes to allocate
Returns:
BX : Offset of registered memory if success,
AL : Status (J_OK, J_NO_MEMORY)
J_FREE_MEM
Releases Janus Memory
Expects:
AL : Type of memory to free
BX : Offset of Memory to free
Returns:
Crash if offset/type was wrong (J_GOODBYE, later)
J_SET_PARAM
Set the default parameter memory pointer
Expects:
AL : Janus Service Number to support
BX : Default Offset of Param Memory to install
Returns:
AL : Status (J_OK, J_NO_SERVICE)
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