[HECnet] Reading RT11 files under Windows or Linux

[Dave McGuire]

On 4/22/21 6:16 AM, Johnny Billquist wrote:
> The 86x0 do load all microcode from the FE at startup time. It takes a
> little while to boot an 86x0 because of this. The power system is also
> software controlled, and at power up, only a single power supply is on.
> Everything else is turned on by the FE at a later stage. Fun to watch
> the system start up. Slowly, LED after LED lights up, as different parts
> gets initialized.

  This is the way IBM mainframes (post-S/390, and a few earlier than
that) work too.  You've probably seen the ones with the laptops built
into the front of the CPU cabinet; they run OS/2 up to the z890, and
after that they run Linux.  They inject the microcode into the hardware
as a part of the POR (Power-On Reset) process.  Booting (er, IPLing)
them takes quite a while, depending on the configuration.

  That's how IBM turns them into zero-resale-value bricks when at
decommissioning time.

> I just love that machine. :-)

  I wish there were more of them around. :-(

           -Dave

-- 
Dave McGuire, AK4HZ
New Kensington, PA