PCjs Machines
Home of the original IBM PC emulator for browsers.
DEC MicroVAX 3900 (KA655) with OpenVMS VAX
Log in with
SYSTEM/QUOKKA1953The machine boots itself: the KA655’s self-tests first, then OpenVMS, about a minute to the
Username:prompt. Click the terminal before typing.
The machine below is a DEC MicroVAX 3900, the Q22-bus VAX built around the KA655 CPU module:
a CVAX 78034 at 3.125 MHz with the CFPA floating-point accelerator, the CMCTL memory controller, the
CQBIC Qbus interface, and the KA655 console/diagnostic ROM at physical 0x20040000.
Attached devices:
- RQDX3 MSCP Disk Controller, with an OpenVMS VAX V5.5 system disk
auto-mounted on
DUA0: - The console serial line on
OPA0:, as a glass TTY — DCL and the boot stream render correctly, but screen programs (EDT, EVE, NOTES) do not paint
The disk image is fetched read-only; writes go to an in-memory copy-on-write overlay that vanishes
when you close the tab. Set autoBoot="false" on the <cpu> element of
machine.xml if you would rather stop at the KA655’s >>> prompt and boot by hand.
[PCjs Machine "vax3900"]
Waiting for machine "vax3900" to load....
The port, the media it loads, and how to run it locally are described on the DEC VAX page.