/* gri_defs.h: GRI-909 simulator definitions 

   Copyright (c) 2001-2003, Robert M. Supnik

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   Software is furnished to do so, subject to the following conditions:

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   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
   ROBERT M SUPNIK BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
   IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
   CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

   Except as contained in this notice, the name of Robert M Supnik shall not
   be used in advertising or otherwise to promote the sale, use or other dealings
   in this Software without prior written authorization from Robert M Supnik.

   25-Apr-03	RMS	Revised for extended file support
   19-Sep-02	RMS	Fixed declarations in gdev structure

   There are several discrepancies between the original GRI-909 Reference
   Manual of 1969 and the only surviving code sample, the MIT Crystal Growing
   System of 1972:

   1. Ref Manual documents two GR's at codes 26-27; MITCS documents six GR's
      at 30-35.
   2. Ref Manual documents only unsigned overflow (carry) for arithmetic
      operator; MITCS uses both unsigned overflow (AOV) and signed overflow
      (SOV).
   3. Ref Manual documents a ROM-subroutine multiply operator and mentions
      but does not document a "fast multiply"; MITCS uses an extended
      arithmetic operator with multiply, divide, and shifts.  The behavior
      of the extended arithmetic operator can only be inferred partially;
      the shifts are never used, and there is no indication of how divide
      overflow is handled.

   The simulator follows the code in these instances.

   Outstanding issues:

   1. Is there any interaction between the byte swapper and the byte packer?
   2. Is SOV testable even if the FOA is not ADD?
   3. How does the EAO handle divide overflow?
   4. What are the other EAO functions beside multiply and divide?
*/

#include "sim_defs.h"					/* simulator defns */

/* Simulator stop codes */

#define STOP_DEV	1				/* must be 1 */
#define STOP_HALT	2				/* HALT */
#define STOP_IBKPT	3				/* breakpoint */
#define STOP_ILLINT	4				/* illegal intr */

/* Memory */

#define MAXMEMSIZE	32768				/* max memory size */
#define AMASK		077777				/* logical addr mask */
#define MEMSIZE		(cpu_unit.capac)		/* actual memory size */
#define MEM_ADDR_OK(x)	(((uint32) (x)) < MEMSIZE)

/* Architectural constants */

#define SIGN		0100000				/* sign */
#define DMASK		0177777				/* data mask */
#define CBIT		(DMASK + 1)			/* carry bit */

/* Instruction format */

#define I_M_SRC		077				/* source */
#define I_V_SRC		10
#define I_GETSRC(x)	(((x) >> I_V_SRC) & I_M_SRC)
#define I_M_OP		017				/* operator */
#define I_V_OP		6
#define I_GETOP(x)	(((x) >> I_V_OP) & I_M_OP)
#define I_M_DST		077				/* destination */
#define I_V_DST		0
#define I_GETDST(x)	(((x) >> I_V_DST) & I_M_DST)
#define SF_V_REASON	1				/* SF reason */

/* IO return */

#define IORETURN(f,v)	((f)? (v): SCPE_OK)		/* stop on error */

/* Operators */

#define U_ZERO		000				/* zero */
#define U_IR		001				/* instruction reg */
#define U_FSK		002				/* func out/skip */
#define U_TRP		003				/* trap */
#define U_ISR		004				/* intr status */
#define U_MA		005				/* mem addr */
#define U_MEM		006				/* mem data */
#define U_SC		007				/* seq counter */
#define U_SWR		010				/* switch register */
#define U_AX		011				/* arith in 1 */
#define U_AY		012				/* arith in 2 */
#define U_AO		013				/* arith out */
#define U_EAO		014				/* ext arith */
#define U_MSR		017				/* machine status */
#define U_BSW		024				/* byte swap */
#define U_BPK		025				/* byte pack */
/* #define U_GR		026				/* dual general regs */
#define U_GR		030				/* hex general regs */
#define U_RTC		075				/* clock */
#define U_HS		076				/* paper tape */
#define U_TTY		077				/* console */

struct gdev {
	uint32	(*Src)(uint32);				/* source */
	t_stat	(*Dst)(uint32, uint32);			/* dest */
	t_stat	(*FO)(uint32);				/* func out */
	uint32	(*SF)(uint32);				/* skip func */
};

/* Trap (jump) */

#define TRP_DIR		00				/* direct */
#define TRP_DEF		01				/* defer */

/* Interrupt status */

#define ISR_OFF		01				/* int off */
#define ISR_ON		02				/* int on */

/* Bus modifiers */

#define BUS_COM		002				/* complement */
#define BUS_FNC		014				/* function mask */
#define BUS_P1		004				/* + 1 */
#define BUS_L1		010				/* rotate left */
#define BUS_R1		014				/* rotate right */

/* Memory address modes */

#define MEM_MOD		03
#define MEM_DIR		00				/* direct */
#define MEM_DEF		01				/* defer */
#define MEM_IMM		02				/* immediate */
#define MEM_IDF		03				/* immediate defer */

/* Arithmetic unit */

#define FO_V_FOA	8				/* arith func */
#define FO_M_FOA	03
#define OP_GET_FOA(x)	(((x) >> (FO_V_FOA - I_V_OP)) & FO_M_FOA)
#define AO_ADD		00				/* add */
#define AO_AND		01				/* and */
#define AO_XOR		02				/* xor */
#define AO_IOR		03				/* or */
#define EAO_MUL		01				/* multiply */
#define EAO_DIV		02				/* divide */
#define EAO_ASR		03				/* arith rshft */

/* Machine status */

#define MSR_V_BOV	15				/* bus carry */
#define MSR_BOV		(1u << MSR_V_BOV)
#define MSR_V_L		14				/* bus link */
#define MSR_L		(1u << MSR_V_L)			/* bus link */
#define MSR_V_FOA	8				/* arith func */
#define MSR_M_FOA	03
#define MSR_V_AOV	0				/* arith carry */
#define MSR_AOV		(1u << MSR_V_AOV)
#define MSR_GET_FOA(x)	(((x) >> MSR_V_FOA) & MSR_M_FOA)
#define MSR_PUT_FOA(x,n)	(((x) & ~(MSR_M_FOA << MSR_V_FOA)) | \
			(((n) & MSR_M_FOA) << MSR_V_FOA))

/* Real time clock */

#define RTC_OFF		001				/* off */
#define RTC_ON		002				/* clock on */
#define RTC_OV		010				/* clock flag */
#define RTC_CTR		0103				/* counter */

/* Terminal */

#define TTY_ORDY	002				/* output flag */
#define TTY_IRDY	010				/* input flag */

/* Paper tape */

#define PT_STRT		001				/* start reader */
#define PT_ORDY		002				/* output flag */
#define PT_IRDY		010				/* input flag */

/* Interrupt masks (ISR) */

#define INT_V_TTO	0				/* console out */
#define INT_V_TTI	1				/* console in */
#define INT_V_HSP	2				/* paper tape punch */
#define INT_V_HSR	3				/* paper tape reader */
#define INT_V_RTC	11				/* clock */
#define INT_V_NODEF	16				/* nodefer */
#define INT_V_ON	17				/* enable */
#define INT_TTO		(1u << INT_V_TTO)
#define INT_TTI		(1u << INT_V_TTI)
#define INT_HSP		(1u << INT_V_HSP)
#define INT_HSR		(1u << INT_V_HSR)
#define INT_RTC		(1u << INT_V_RTC)
#define INT_NODEF	(1u << INT_V_NODEF)
#define INT_ON		(1u << INT_V_ON)
#define INT_PENDING	(INT_ON | INT_NODEF)

/* Vectors */

#define VEC_BKP		0000				/* breakpoint */
#define VEC_TTO		0011				/* console out */
#define VEC_TTI		0014				/* console in */
#define VEC_HSP		0017				/* paper tape punch */
#define VEC_HSR		0022				/* paper tape reader */
#define VEC_RTC		0100				/* clock */
