x86_64 physical serial port speed problem.

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sms
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x86_64 physical serial port speed problem.

Post by sms » Mon Feb 03, 2025 7:51 pm

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   I accept that none of this is supported, but I'd be interested in any
clever ideas.

   I recently tried to boot a V9.2-3 installation DVD on a Dell 5820
workstation.  The result seems to be a scrambled Boot Manager display. 
Keyboard activity has an effect, but it's all illegible.

   I then tried to connect a serial terminal (emulator) to the serial
port on the Dell system (which Windows calls "COM 1"), which also
displays line-noise, at best.  But blindly-typed activity on the
directly-connected USB keyboard does seem to generate more line-noise on
the serial port (as well as more scrambled graphics noise).

   According to "VSI OpenVMS x86-64 Boot Manager User Guide" (Operating
System and Version: VSI OpenVMS x86-64 V9.2-2):

      The Boot Manager and UEFI use 115200 baud, 8 bit, 1 stop bit, no
      parity. It will auto-negotiage [sic] other baud rates.

   Sadly, my easiest-to-use "terminal" serial port is on a DECserver
DS90M terminal server (SET HOST /LAT on an IA64 system), which does not
go that fast. HELP SET PORT SPEED on the DS90M says:

[...]
Possible speed values:

75, 110, 134, 150, 300, 600, 1200, 1800, 2000, 2400, 4800, 9600, 19200,
38400, 57600, 115200.

Default: 9600.
[...]

but that's less than true:

Local> set port 3 speed 115200
Local -703- Value invalid or out of range, "115200"

   I've seen no evidence of any "auto-negotiage" behavior for a wide
variety of (valid) serial port speeds.

   So, while I investigate how to arrange a connection to a faster
serial "terminal", if anyone knows of any Boot Manager command(s) (which
I could type blindly into the guest console) to change either the
graphical display or serial port characteristics, I'd be interested.

   Presumably, something else will fail if I can get a functional
console, and try BOOT, but I'd like to get that far before giving up.


roberbrooks
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Re: x86_64 physical serial port speed problem.

Post by roberbrooks » Mon Feb 03, 2025 9:58 pm

Potentially useless suggestion:

What happens if you try using the Dell iDRAC mechanism to access the system, rather than using the serial port?
--
-- Rob


Topic author
sms
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Re: x86_64 physical serial port speed problem.

Post by sms » Mon Feb 03, 2025 11:31 pm

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> [...] the Dell iDRAC mechanism [...]

   Never heard of it, but it seems that "iDRAC is embedded in every
PowerEdge server", and the Dell Precision 5820 workstation is not one of
those.  And it doesn't appear to be free.

https://www.dell.com/en-us/lp/dt/open-manage-idrac

https://www.delltechnologies.com/asset/en-us/solutions/infrastructure-solutions/briefs-summaries/integrated_dellemc_remote_access_controller.pdf


pocketprobe
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Re: x86_64 physical serial port speed problem.

Post by pocketprobe » Tue Feb 04, 2025 10:20 am

Other than for trying things like multi-writer disks, or seeing if a bug is specific to my running VMS on bare metal I've run VMS nigh exclusively on bare metal, both on a couple of "white boxes", and on a ProLiant Ml150 Gen9.

I too have experienced the scrambled display on a previous version of BOOTMGR [V9.2-2]. I would ask what you are using for a graphics adapter but I had worked around this prior by using an older version of BOOTMGR. For your precision, look around in your BIOS/UEFI/Firmware for CSM or (legacy) compatibility and try it the other way. If you can get a clear display, the vga console is an option.

As far as the serial port speed goes, between inexpensive usb->serial adapters and a VT520, BOOTMGR and later VMS do in fact send bytes out at 115200,8,n,1. The last time I had tried to change the serial port speed, OPA0 had stopped responding to serial data, but that may have been my inexperience a year and a half ago.

Once you have the serial port up and running, in my experiences with running X86VMS on bare metal BOOTMGR will not respond to input from the serial port, but will send out your typed keystrokes to the serial port.

If you do get booted into the installer, you will probably find that VMS hasn't found any disks to install to, but I've mentioned this in my original thread about my adventures in doing this.

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