@database "680x0"
@master "VIF:Mu/MuManual/Autodocs/680x0.doc"

@Node Main "680x0.doc"
    @{" --Background-- " Link "--Background--"}
    @{" CPUType() " Link "CPUType()"}
    @{" FPUType() " Link "FPUType()"}
    @{" MMUType() " Link "MMUType()"}
    @{" SetFPUExceptions() " Link "SetFPUExceptions()"}
@EndNode

@Node "--Background--" "680x0.library/--Background--"

@{b}    PURPOSE@{ub}

	This library is the generic processor support library for all
	Amigas and all CPU types. Its purpose is to determinate which
	CPU, FPU and MMU type is installed, and to load the processor
	specific support code in form of the 68000.library, 
	the 68010.library, the 68020.library, the 68030.library, the
	68040.library or the 68060.library. It does not include CPU
	specific code instead, but re-routes all its calls to the processor
	specific library to allow CPU/FPU/MMU independent code. It loads
	also the mmu.library on startup to install the MMU specific
	functions.

	This library provides user-callable functions to determinate the
	CPU/FPU and MMU type available. The results are more precise than
	those that can be found in SysBase->AttnFlags. Furthermore, the
	library controls the FPU exceptions.

	The 680x0.library is usually loaded by "SetPatch" on startup and
	remains in the system. It then checks the available hardware and
	loads the CPU and MMU specific drivers.


@EndNode

@Node "CPUType()" "680x0.library/CPUType"
    
@{b}    NAME@{ub}
	CPUType	 -   return information about the available CPU

@{b}    SYNOPSIS@{ub}
	cpu = CPUType ( );

	char CPUType ( void );

@{b}    FUNCTION@{ub}
	This function returns a one-bit identifier about the available CPU.
	It currently knows the 68000, 68010, 68020, 68030, 68040 and 
	68060.

@{b}    INPUTS@{ub}
	none.

@{b}    RESULTS@{ub}
	The CPU type found. One of the following identifiers is returned:

	CPUTYPE_68000       /* a plain 68000*/
	CPUTYPE_68010       /* a 68010  */
	CPUTYPE_68020       /* a 68020  */
	CPUTYPE_68030       /* a 68030  */
	CPUTYPE_68040       /* a 68040  */
	CPUTYPE_68060       /* a 68060  */

@{b}    NOTES@{ub}
	Unlike some third-party libraries, this result code will be correct
	even for the 68060.

@{b}    BUGS@{ub}
	Does currently not support a PPC.

@{b}    SEE ALSO@{ub}
	libraries/680x0.h, exec/execbase.h

@EndNode

@Node "FPUType()" "680x0.library/FPUType"
    
@{b}    NAME@{ub}
	FPUType	 -   return information about the available FPU

@{b}    SYNOPSIS@{ub}
	fpu = FPUType ( );

	char FPUType ( void );

@{b}    FUNCTION@{ub}
	This function returns a one-bit identifier of the available FPU.
	It currently knows the 68881, 68882 and the build-in FPUs of the
	68040 and 68060.

@{b}    INPUTS@{ub}
	none.

@{b}    RESULTS@{ub}
	The FPU type found. One of the following identifiers is returned:

	FPUTYPE_NONE    /* no FPU available */
	FPUTYPE_68881   /* the 68881 external FPU   */
	FPUTYPE_68882   /* the advanced edition of this chip */
	FPUTYPE_68040   /* the 68040 buildin FPU    */
	FPUTYPE_68060   /* the 68060 buildin FPU    */

@{b}    NOTES@{ub}
	This function works differently than SysBase->AttnFlags. It will
	return FPUTYPE_68040 or FPUTYPE_68060 if a 68040 or 68060 FPU is
	in the system, regardless whether the processor support code has
	been loaded and the 68881/68882 instructions can be emulated in
	software. This should be checked in SysBase->AttnFlags, if 
	required.

@{b}    BUGS@{ub}
	Does currently not support a PPC.

@{b}    SEE ALSO@{ub}
	libraries/680x0.h, exec/execbase.h

@EndNode

@Node "MMUType()" "680x0.library/MMUType"

@{b}    NAME@{ub}
	MMUType - return the type of the MMU available in the system.

@{b}    SYNOPSIS@{ub}
	mmu = GetMMUType( );
			

	char GetMMUType( void );

@{b}    FUNCTION@{ub}
	Returns an identifier for the MMU available in the system or
	NUL in case no MMU is installed.

@{b}    INPUTS@{ub}
	none.

@{b}    RETURNS@{ub}
	a character identifying the MMU type:

	MUTYPE_NONE		no working MMU detected.
	MUTYPE_68851		a 68020 system with an external 68851
				MMU.
	MUTYPE_68030		a 68030 MMU.
	MUTYPE_68040		the internal 68040 MMU.
	MUTYPE_68060		the 68060 MMU.

@{b}    NOTES@{ub}
	This call is directly re-routed to the mmu.library @{"GetMMUType()" Link "mmu/GetMMUType()"}
	call. If the mmu.library is not available, it will return
	MUTYPE_NONE.

	The mmu library is smart enough to detect EC processors without a
	working MMU, but the library does not detect multiple CPUs in the
	system. (How?)

@{b}    BUGS@{ub}

@{b}    SEE ALSO@{ub}
	libraries/680x0.h, mmu/mmubase.h

@EndNode

@Node "SetFPUExceptions()" "680x0.library/SetFPUExceptions"

@{b}    NAME@{ub}
	SetFPUExceptions	-   control the generation of FPU exceptions

@{b}    SYNOPSIS@{ub}
	oldflags = SetFPUExceptions ( flags , mask );
	d0				d0     d1

	ULONG SetFPUExceptions ( ULONG , ULONG );

@{b}    FUNCTION@{ub}
	This function disables or enables various exceptions a MC68K
	FPU might generate. The purpose of this function is mainly to
	enable workarounds for badly written software.

@{b}    INPUTS@{ub}
	flags	-	A ULONG bit mask of the exceptions to disable. A
			set bit disables the corresponding exception.
	mask	-	A mask longword of the flags that are to be changed.
			A set bit indicates that the corresponding bit in
			flags mask is valid.

	The following bits are currently defined:

	FPUCtrlB_BSUN   0L      Disable the branch or set on unordered 
				exception.
	FPUCtrlB_INEX   1L      Disable the inexact result exception.
	FPUCtrlB_DIVZ   2L      Disable the divide by zero exception.
	FPUCtrlB_UNFL   3L      Disable the underflow exception.
	FPUCtrlB_OVFL   4L      Disable the overflow exception.
	FPUCtrlB_SNAN   5L      Disable the signalling NAN exception.
	FPUCtrlB_OPERR  6L      Disable the operand error.

@{b}    RESULTS@{ub}
	the old settings of the exception mask.

@{b}    NOTES@{ub}
	This function is directly re-routed to the CPU specific driver, i.e.
	either the 68040, the 68060, the 68020 or the 68030.library. It
	does not touch the FPU itself. If the driver is not available, or
	does not allow the change the FPU exception mask, this procedure
	does nothing and returns "0".

@{b}    BUGS@{ub}

@{b}    SEE ALSO@{ub}
	libraries/68040.h, libraries/680x0.h,
	the Motorola 68040 manual.

@EndNode