github.com/simh.simh
1
0
Fork 0
mirror of https://github.com/simh/simh.git synced 2026-01-26 12:02:14 +00:00
Code Releases Activity

Notes For V3.2-2

Browse Source 
RESTRICTION: The PDP-15 FPP is only partially debugged.  Do NOT
enable this feature for normal operations.
RESTRICTION: The HP DS disk is not debugged.  DO NOT enable this
feature under any circumstances.

1. New Features in 3.2-2

None

2. Bugs Fixed in 3.2-2

2.1 SCP

- Fixed problem ATTACHing to read-only files (found by John Dundas)
- Fixed problems in Windows terminal code (found by Dave Bryan)
- Fixed problem in big-endian reads (reported by Scott Bailey)

2.2 GRI-909

- Updated MSR to include SOV
- Updated EAO to include additional functions

2.2 HP2100 (from Dave Bryan)

- Generalized control character handling for console terminal

2.3 VAX

- Fixed bad block initialization routine
This commit is contained in:
Bob Supnik
2004-07-17 11:55:00 -07:00
committed by Mark Pizzolato
parent e2ba672610
commit 2688f2d26e
11 changed files with 193 additions and 97 deletions
Download Patch File Download Diff File Expand all files Collapse all files

34
GRI/gri_cpu.c
View File

@@ -25,6 +25,7 @@
cpu GRI-909 CPU
17-Jul-04 RMS Revised MSR, EAO based on additional documentation
14-Mar-03 RMS Fixed bug in SC queue tracking
The system state for the GRI-909 is:
@@ -731,6 +732,9 @@ case AO_IOR:
break; }
if ((AX + AY) & CBIT) MSR = MSR | MSR_AOV; /* always calc AOV */
else MSR = MSR & ~MSR_AOV;
if (SIGN & ((AX ^ (AX + AY)) & (~AX ^ AY))) /* always calc SOV */
MSR = MSR | MSR_SOV;
else MSR = MSR & ~MSR_SOV;
return t;
}
@@ -778,21 +782,41 @@ if (cpu_unit.flags & UNIT_NOEAO) return stop_opr; /* EAO installed? */
if (op == EAO_MUL) { /* mul? */
t = AX * AY; /* AX * AY */
AX = (t >> 16) & DMASK; /* to AX'GR1 */
GR[0] = t & DMASK; }
if (op == EAO_DIV) { /* div? */
GR[0] = t & DMASK;
}
else if (op == EAO_DIV) { /* div? */
if (AY && (AX < AY)) {
t = (AX << 16) | GR[0]; /* AX'GR1 / AY */
GR[0] = t / AY; /* quo to GR1 */
AX = t % AY; } /* rem to AX */
AX = t % AY; /* rem to AX */
MSR = MSR & ~MSR_L; } /* clear link */
else MSR = MSR | MSR_L; /* set link */
}
else if (op == EAO_ARS) { /* arith right? */
t = 0; /* shift limiter */
if (AX & SIGN) MSR = MSR | MSR_L; /* L = sign */
else MSR = MSR & ~MSR_L;
do { /* shift one bit */
AY = ((AY >> 1) | (AX << 15)) & DMASK;
AX = (AX & SIGN) | (AX >> 1);
GR[0] = (GR[0] + 1) & DMASK; }
while (GR[0] && (++t < 32)); /* until cnt or limit */
}
else if (op == EAO_NORM) { /* norm? */
if ((AX | AY) != 0) { /* can normalize? */
while ((AX & SIGN) != ((AX << 1) & SIGN)) { /* until AX15 != AX14 */
AX = ((AX << 1) | (AY >> 15)) & DMASK;
AY = (AY << 1) & DMASK;
GR[0] = (GR[0] + 1) & DMASK; } }
}
ao_update ();
return SCPE_OK;
}
uint32 ao_sf (uint32 op)
{
if (((op & 2) && (MSR & MSR_AOV)) || /* arith carry? */
((op & 4) && (SIGN & /* arith overflow? */
((AX ^ (AX + AY)) & (~AX ^ AY))))) return 1;
((op & 4) && (MSR & MSR_SOV))) return 1; /* arith overflow? */
return 0;
}

29
GRI/gri_defs.h
View File

@@ -28,28 +28,29 @@
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:
System of 1972. These discrepancies were clarified by later documentation:
1. Ref Manual documents two GR's at codes 26-27; MITCS documents six GR's
at 30-35.
at 30-35. Answer: 6 GR's, 26-27 were used for character compares.
2. Ref Manual documents only unsigned overflow (carry) for arithmetic
operator; MITCS uses both unsigned overflow (AOV) and signed overflow
(SOV).
(SOV). Answer: signed and unsigned.
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
arithmetic operator with multiply, divide, and shift. 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.
the shift is never used, and there is no indication of how divide
overflow is handled. Answer: EAO is a package of ROM subroutines
with just four functions: multiply, divide, arithmetic right shift,
and normalize.
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?
3. How does the EAO handle divide overflow? Answer: set link.
4. What are the other EAO functions beside multiply and divide?
Answer: arithmetic right shift, normalize.
*/
#include "sim_defs.h" /* simulator defns */
@@ -109,7 +110,6 @@
#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 */
@@ -159,17 +159,20 @@ struct gdev {
#define AO_IOR 03 /* or */
#define EAO_MUL 01 /* multiply */
#define EAO_DIV 02 /* divide */
#define EAO_ASR 03 /* arith rshft */
#define EAO_ARS 03 /* arith rshft */
#define EAO_NORM 04 /* normalize */
/* 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_SOV 1 /* arith ovflo */
#define MSR_V_AOV 0 /* arith carry */
#define MSR_BOV (1u << MSR_V_BOV)
#define MSR_L (1u << MSR_V_L)
#define MSR_SOV (1u << MSR_V_SOV)
#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)) | \