source: buchla-68k/include/fpu.h

/*
   =============================================================================
        fpu.h -- FPU definitions
        Version 4 -- 1987-11-05 -- D.N. Lynx Crowe
   =============================================================================
*/

#pragma once

/* preprocessor functions */

#define FPUVAL(x)       ((x) << 5)

/* FPU data areas (word offsets) */

#define FPU_OWST        0x00000000L     /* waveshape tables */
#define FPU_OFNC        0x00002000L     /* functions */
#define FPU_OINT        0x00002000L     /* interrupt read address */
#define FPU_OICL        0x00003000L     /* interrupt clear address */
#define FPU_OCFG        0x00002FF0L     /* configuration words */
#define FPU_OSYN        0x00002FFFL     /* sync word */

/* FPU time limits */

#define FPU_MAXT        0xFFF0  /* FPU maximum time (65520 ms) */
#define FPU_MINT        0x800F  /* FPU minimum time (1 ms) */

/* FPU value limits */

#define VALMAX          (1000 << 5)
#define VALMIN          (-VALMAX)

/* FPU data types */

#define FPU_TCTL        0       /* control */
#define FPU_TNV0        1       /* new value[0] -- '10' in new value select */
#define FPU_TCV1        4       /* voltage 1 */
#define FPU_TSF1        5       /* scale factor 1 */
#define FPU_TCV2        6       /* voltage 2 */
#define FPU_TSF2        7       /* scale factor 2 */
#define FPU_TCV3        8       /* voltage 3 */
#define FPU_TSF3        9       /* scale factor 3 */
#define FPU_TMNT        10      /* time mantissa */
#define FPU_TEXP        11      /* time exponent */
#define FPU_TNV1        14      /* new value[1] -- '01' in new value select */