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DEC VAX 11/780

Digital Equipment VAX 11/780

During January 2002 Merle Pierce drove to Wisconsin to retreive several machines including this VAX 11/780. The VAX 11/780 is the benchmark machine that defined what a MIP (Million Instructions per Second) was. This machine consists of a KA780 CPU, DW780 Unibus Adapter, MS780 Memory with 16 MB RAM, RH780 Massbus Adapter, and an Emulex SC780 SMD disk controller that emulates an RH780. The VAX has a TU81 6250/1600 BPI 9 track 1/2" tape drive and a cabinet containing four Emulex badged Fujitsu Eagle SMD disk drives. The system runs BSD 4.3 UNIX instead of the more usual VMS operating system. The cabinet at the right holds the Unibus expansion rack and a bank of modems.

The image below shows the 11/780 card cage. The 29 slots on the left are the KA780 CPU. The next 6 slots toward the right are the DW780 Unibus Adapter, the next 20 slots are the MS780 memory (16MB), the next 6 slots are the RH780 Massbus adapter for the TU81 tape drive, and the 4 slots on the far right are the Emulex SC780 SMD disk adapter for the Fujitsu Eagle SMD disk drives.

KA780 CPU Card Cage

Slot

Part Number Description
1
M8237
TRS,TERMINATOR & SILO
2
M8218
KA780,SBL,CPU SBI LOW BITS INTERFACE
3
M8219
KA780,SBH,SBI (SYNCHRONOUS BACK PLANE INTERFACE),HIGH BITS
4
M8220
KA780,CAM,CACHE ADDRESS MATRIX
5
M8221
KA780,CDM,CACHE DATA MATRIX
6
M8222
KA780,TBM,CPU TRANSLATION BUFFER MATRIX
7
M8223
KA780,IDP,CPU INSTRUCTION DATA PATH
8
M8224
KA780,IRC,CPU INSTRUCTION DECODE & CLOCKS
9
M8225
KA780,DBP,CPU DATA PATH
10
M8226
KA780,DEP,CPU DATA PATH E
11
M8227
KA780,DDP,CPU DATA PATH D
12
M8228
KA780,DCP,CPU DATA PATH C
13
M8229
KA780,DAP,CPU DATA PATH A
14
M8230
KA780,CEH (CONDITION CODES,EXCEPTIONS,HIGH BITS)
15
M8231
KA780,ICL (INTERRUPT CONTROL,LOW BITS)
16
M8232
KA780,CLK (CPU CLOCK)
17
Empty
 
18
Filler
 
19
Empty
 
20
M8238
KU780-A 2K WCS (WRITEABLE CONTROL STORE)
21
Empty
 
22
M8234
KA780, PCS CPU PROM CONTROL STORE
23
M8235
KA780,USC,MICRO SEQUENCER CONTROL
24
Filler
 
25
Filler
 
26
Filler
 
27
Filler
 
28
Filler
 
29
M8236
KA780,CIB,CPU CONSOLE INTERFACE

DW780 Unibus Adapter Card Cage

Slot

Part Number Description
1
M8270
DW780-A,USI,UNIBUS ADAPTER SBI INTERFACE
2
M8271
DW780-A,UCB,UNIBUS ADAPTER CONTROL
3
M8272
DW780-A,UMD,UNIBUS ADAPTER MAP & DATA PATH
4
M8273
DW780-A,UAI,UNIBUS ADAPTER ADDRESS
5
Empty
Unibus Out
6
Empty
Unibus In

MS780 Memory Card Cage, 16 MB

Slot

Part Number Description
1
Empty
 
2
M8373
256K X 39 BIT ARRAY, NEC 64K PARTS
3
MMI 303-0327 256K X 39 BIT ARRAY
4
MMI 303-0327 256K X 39 BIT ARRAY
5
MMI 303-0327 256K X 39 BIT ARRAY
6
MMI 303-0327 256K X 39 BIT ARRAY
7
MMI 303-0327 256K X 39 BIT ARRAY
8
MMI 303-0327 256K X 39 BIT ARRAY
9
M8373
256K X 39 BIT ARRAY, NEC 64K PARTS
10
M8375
MEMORY CONTROL (Lower)
11
M8376
SBI INTERFACE
12
M8375
MEMORY CONTROL (Upper)
13
M8373
256K X 39 BIT ARRAY, NEC 64K PARTS
14
MMI 303-0327 256K X 39 BIT ARRAY
15
MMI 303-0327 256K X 39 BIT ARRAY
16
MMI 303-0327 256K X 39 BIT ARRAY
17
MMI 303-0327 256K X 39 BIT ARRAY
18
MMI 303-0327 256K X 39 BIT ARRAY
19
MMI 303-0327 256K X 39 BIT ARRAY
20
M8373
256K X 39 BIT ARRAY, NEC 64K PARTS

RH780 Massbus Controller Card Cage

Slot

Part Number Description
1
M8275
MSI MASSBUS ADAPTER SBI INTERFACE
2
M8276
MIR MASSBUS INTERNAL REGISTER
3
M8277
MDP MASSBUS DATA PATHS
4
M8278
MCP MASSBUS CONTROL PATHS
5
Empty
 
6
Empty
Massbus

Emulex SC780 V-Master/780 Controller Card Cage

Slot

Part Number Description
1
7810401
Emulex Bus Interface Board
2
7810402
Emulex Bus Translator Board
3
7810410
Emulex SMD Disk Adapter
4
Empty
 

 

 

Hover your mouse pointer over a section of the card cage below to see what it is.

 

The Fujitsu Eagle SMD Disk Drives that are connected to the Emulex SC780 Controller.
 
The DEC TU78 Tape Drive that is connected to the RH78 Massbus Controller.
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