INSERT[D0LANG];
NOMIDASINIT;
TITLE[d0mem];
*last edited by CT June 11, 1979
SETTASK[17];

RV[REFR,77];	*memory refresh address

*The following registers hold the volatile state of the processor on a fault: 
RV[RXALU,76];	*ALU result and SALUF
RV[RXAPC,75];	*APCTask&APC
RV[RXCTASK,74];	*CTASK.NCIA
RV[RXPPB,73];	*Page,Parity,BootReason
RV[RXSTK,72];	*Stackpointer

RV[RTMP,71];	*temporary

*The following registers are used for D0-Midas communication (RTMP is also used):
RV[RWSTAT,70];	*status register
RV[RDATA,67];	*holds data

*FFault determines how faults will be treated when programs are running.  If it is
*zero, all faults will be reported to Midas.  If FFault is nonzero, the kernel will
*send control through location 120 when a fault occurs and PARITY # 0 (faults with
*PARITY = 0 are breakpoints).
RV[FFAULT,66];

*Registers between 360 and 365 are used by the Midas overlays.  The following 
*registers, used by WriteMI,  are also in this range.
RV[RADDR,65];
RV[Stack5,65];

RV[RCNT,64];
RV[STACK4,64];

RV[RW0,63];
RV[STACK3,63];

RV[RW1,62];
RV[STACK2,62];

RV[STACK1,61];
MC[pStk1,361]; *pointer to stack1
RV[STACK0,60];


*Constants for Recv and Send
MC[RecvByte,12];
MC[RecvWord,16];
MC[SendByte,21];
MC[SendWord,25];

*The following are at fixed locations in Kernel.mc:
UserFault:	Return, AT[120];
NextCom:	Return, AT[7404];
Send:	Return, AT[7460];
Recv:	Return, AT[7464];

*d0mem overlay
*Used by Midas to do memory references.

OverlayArea:
	RWSTAT ← RecvByte, call[Recv], at[7500]; *get code (4,5, or 6)
	dispatch[RDATA,14,4], at[7501];
	disp[OverlayArea], at[7502];
Intlk:	Stack0 ← Stack0, goto[NextCom], at[7503];
	PFetch4[Stack4,Stack0,0], goto[Intlk], at[7504];
	PStore4[Stack4,Stack0,0], goto[Intlk], at[7505];
	XMap[Stack4,Stack0,0], goto[Intlk], at[7506];


	END;