View source for VAX-11/780

{{InfoboxVAX-Data
| name = VAX-11/780
| Announcement = October 1977
| Codename = Star
| OS-support-VMS = VMS V1.5
| CPU-name-VMS = KA780
| Num-proc = 1
| CPU-technology = Bipolar Schottky
| CPU-cycle = 200ns [[#ref_1|[1]]]
| Instruction-buffer = 8 bytes [[#ref_1|[1]]]
| Translation-buffer = 128 entries [[#ref_1|[1]]]
| Control-store = 4K 99-bit words [[#ref_1|[1]]]
| Gate-delay = 3ns
| UWCS = 2K 99-bit words [[#ref_1|[1]]]
| Cache = 8KB [[#ref_1|[1]]]
| Compatibility-mode = Yes [[#ref_1|[1]]]
| Console-processor = LSI-11 [[#ref_1|[1]]]
| Console-device = RX01 [[#ref_1|[1]]]
| Minimum-memory = 2MB
| Maximum-memory = 64MB
| Physical-address-lines = 30
| Memory-checking = 8-bit ECC/longword [[#ref_1|[1]]]
| Max-I/O-throughput = 5.0MB/s
| BUS-MASSBUS = 4 @ 2.0MB/s
| BUS-UNIBUS = 4 @ 1.5MB/s
| LAN-support = optional
| VUPs = 1.0 [[#ref_2|[2]]]
}}

[[Image:Vax11-780_2.png|thumb|A 'typical' VAX-11/780 marketing image]]

The '''VAX-11/780''' was the first member to ship of the VAX-11 family of larger computers. The VAX series was conceived as the successor to the successful [[PDP-11]] series of [[minicomputer]]s, and in order to make the VAX seem more PDP-11 friendly, they retained the -11 moniker for the first VAXen, hence the -11/780 designation.

It was announced on October 25<sup>th</sup>, 1977 at [[Digital Equipment Corporation]]'s Annual Meeting of Shareholders.[[#ref_4|[4]]]

One of the main design goals was to increase the address space available, in fact the VAX acronym originally stood for Virtual Address eXtension).[[#ref_3|[3]]]

The first VAX-11/780 systems shipped with one quarter of a megabyte of memory, built from 4Kb chips.[[#ref_3|[3]]]

The 11/780 didn't have normal firmware, instead it loaded its [[microcode]] from floppy. There was also the [[VAX-11/785]], which was an upgraded version.

The VAX-11/780 was given the codename "Star" and its operating system, VAX/VMS, was codenamed "Starlet".[[#ref_4|[4]]] VAX/VMS Version V1.0 shipped in 1978, along with the first revenue-ship 11/780s.

"In 1981, he [George H. Goble] wired together the backplanes of two DEC VAX-11/780's and made the first multi-CPU Unix computer, preceding DEC's dual processor VAX-11/782. The operating system was based on the 4.2 BSD kernel, and the modifications thus made eventually made it into the 4.3 BSD Unix release. At the beginning of the 4.3 BSD user manuals, Bill Joy wrote a special note of thanks to GHG for being courageous enough to put the multi-CPU kernel into a production environment before anyone else did. (However, the frequent crashes for a while inspired the writing of many humorous text files by the Purdue University Electrical Engineering student body, such as "The VAX had a Blowout", to be sung to the tune of London Bridge is Falling Down). The development of the Dual-CPU Unix system was the subject of Goble's Master's thesis. " [https://en.wikipedia.org/wiki/George_H._Goble Article on George H Goble]



==Operating Systems==

[[Image:DEC-VAX-11-780.jpg|thumb|An actual VAX-11/780 system]]

The 11/780 was to ship with VMS 1.0.

* [[VMS]] 1.0 - ?.0
* [[32v]]
* [[Ultrix]]
* [[BSD]] (CSRG flavor) version 3.0 - 4.3
* [[NetBSD]]
* [[OpenBSD]]

==Emulation==

[[SIMH]] is the only known emulator for the 11/780.  SIMH can address up to 128MB of RAM emulating an 11/780.  Also the following peripherals are emulated:

*CPU VAX-11/780 CPU
*TLB translation buffer
*SBI system bus controller
*MCTL0,MTCL1 memory controllers, MS780C with 4MB memory each, or MS780E with 8MB-64MB each
*UBA DW780 Unibus adapter
*MBA0,MBA1 RH780 Massbus adapters
*TODR time-of-day clock
*TMR interval timer
*TTI,TTO console terminal
*RX console RX01 floppy disk
*DZ [[DZ11]] 8-line terminal multiplexer (up to 4)
*CR [[CR11]] card reader
*LPT [[LP11]] line printer
*RP [[RP04]]/05/06/07, RM02/03/05/80 Massbus disks, up to eight drives
*HK [[RK611]]/RK06(7) cartridge disk controller with eight drives
*RL [[RL11]]/RL01(2) cartridge disk controller with four drives
*RQ [[UDA50]] MSCP controller with four drives
*RQB second UDA50 MSCP controller with four drives
*RQC third UDA50 MSCP controller with four drives
*RQD fourth UDA50 MSCP controller with four drives
*RY [[RX211]] floppy disk controller with two drives
*TS [[TS11]] magnetic tape controller with one drive
*TQ [[TUK50]] TMSCP magnetic tape controller with four drives
*TU [[TM03]] tape formatter with eight TE16/TU45/TU77 drives
*XU [[DEUNA]]/[[DELUA]] Ethernet controller
*XUB second [[DEUNA]]/[[DELUA]] Ethernet controller

More information about SIMH's VAX 11/780 emulation can be found [http://simh.trailing-edge.com/pdf/vax780_doc.pdf here].

== Related Documents ==

<div>VAX 11/780 Architecture Handbook Vol. 1 1977-78. EB-07466-20</div>
<div>VAX-11/780 Hardware User's Guide. EK-11780-UG-001</div>
<div>VAX-11/780 Installation Manual. EK-SI780-IN-002</div>
<div>VAX 11/780 Hardware Handbook 1979-80. EB-17835-18</div>
<div>VAX Maintenance Handbook VAX-11/780. EK-VAXV2-HB-002</div>
<div>VAX-11/780 Diagnostic System Technical Description. EK-DS780-TD-001</div>
<div>VAX-11/780 Diagnostic System User's Guide. EK-DS780-UG.002</div>
<div>MS780-E MS780-H Memory Subsystem Technical Description. EP-780EH-TD-002</div>
<div>KA780 Central Processor Technical Description. EK-KA780-TD.001</div>
<div>Translation Buffer, Cache and SBI Control Technical Description (VAX-11/780 Implementation). EK-MM780-TD-001</div>
<div>MS780 Memory System Technical Description. EK-MS780-TD-001</div>
<div>FP780 Floating-Point Accelerator. EK-FP780-TD.001</div>
<div>KC780 Console Interface Board Technical Description. EP-KC780-TD-001</div>
<div>KC780 Family Remote Diagnosis Options Technical Manual. KC780, KC782 and KC785. EK-KC780-TM-007</div>
<div>VAX/11/780 Microprogramming Tools User's Guide. AA-H306B-TE</div>
<div>VAX-11/780 Data Path Description. AA-H307B-TE</div>
<div>VAX-11/780 Sofwtare Installation Guide. AA-M545B-TE</div>
<div>CI750 CI780 Computer Interconnects Maintenance Advisory. EP-CIVAX-RM-001</div>
<div>VAX-11/780 Unibus Adapter Technical Description. EK-DW780-TD.001</div>
<div>RH780 Massbus Adapter Technical Description. EK-RH780-TD-001</div>
<div>Guide to VAX-11/780 System Troubleshooting. EY-2217E-SG-0001</div>
<div>KA780 Field Maintenance Print Set. MP00496</div>
<div>DW780 Field Maintenance Print Set. MP00497</div>
<div>KC780 Field Maintenance Print Set. MP00534</div>
<div>11780 Field Maintenance Print Set. MP00539</div>
<div>MS780-H Field Maintenance Print Set. MP01759</div>

==References==

 <div id="ref_1">[1] VAX Hardware Handbook Volume 1 - 1986. </div>
 <div id="ref_2">[2] Systems & Options Catalog. European Edition. Spring 1990. </div>
 <div id="ref_3">[3] VAX Architecture Reference Manual. Timothy E. Leonard. 1987. EY-3459E-DP. ISBN 0-932376-86-X.
 <div id="ref_4">[4] Nothing Stops It! VAX Open VMS At 20.

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