rtVAX 300.

Somehow, I think this list should have no trouble turning up VAX geeks. I know VAX assembly language well and machine language moderately myself, even.

Depends on the hardware. I gather from the discussion that there are multiple different types of rtVAX. The KA620 uses the same console as the KA630, which is accessed from software with mtpr/mfpr to/from four registers, two status and two data; the underlying UART hardware is either hidden by glue hardware or custom (well, unless there's a UART chip that happens to match, which there might be - see below). Things most UARTs set in software, like baud rate, are set by hardware (there's a rotary switch on the KA6[23]0 cab kit for speed). I'm not sure what "standard SLUs" means across different architectures and buses and such. The standard PDP-11 SLU, to the extent that there is such a thing and to the extent that the info I've found is accurate, is a subset of the VAX console: the status bits that both machines have have the same values in their registers, and the VAX MTPR/MFPR registers correspond 1:1 to the PDP-11 SLU registers (the PR numbers are even in the same order as the PDP-11 addresses). So if there's a chip designed for a PDP-11 SLU, it may well be what the KA620 and/or KA630 uses. None of the UART chips I am (even vaguely) familiar with, like the 8530, fit this description. However, a serial line such as the VAX uses is not a complicated device; I could probably put one together from discrete logic in no more than an hour or two. It could very well be just a small section of one of the custom chips involved. And, of course, rtVAXen other than the KA620 (the KA620 is considered an rtVAX, is it not?) may well use something else. It's not clear to me exactly which model this thread is talking about. /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTML mouse at rodents-montreal.org / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B