Bit of CP/M trivia needed

[Dwight K. Elvey]

>From: "Allison" <ajp166 at bellatlantic.net>
---snip---
>
>All the S100 machine of early origin were front pannel
>(switches and lights) and few had rom/eprom.

Hi Allison
 Yes, eproms were expensive.
 
>  Most all 
>used hardware IO and a hand toggled in boot (assuming 
>the controller didn't have a bootrom).  Most of the 
>people doing it were running far lighter hardware 
>than you have there.  Most of the heavey geeks were 
>using stuff like PT ALS8 systems to bootstrap to 
>CP/M for the first time.  Me I plodded through a 
>lot of hand toggling plus my tape based system.

 I did this also to get my first level of bootstrap
running and saved to the disk. I'll admit that I did
take advantage of having a PC laptop to use as
large external data storage to minimize the amount
of toggling. Still, I made a formatting program,
first level bootstrap and BIOS through the front panel
with the serial input. I used no monitor program,
just a simple serial-input-to-memory program that I
toggled in.
 I can imagine how much more effort there would have
been without the external mass storage. Even a minimum
of toggling and paper tape would be quite painful.


>Even then it was load the available image on SSSD 8"
>then overlay the drivers by hand (switches or monitor 
>program) then save it to whatever before a trial boot.
>Early on there were very few disk systems and fewer 
>that were plug and go for CP/M.  Usual case was 
>migrating from available hardware and non-CP/M software
>to CP/M.  Did that for both 8" and NS* 5.25 and also the 
>NEC PDA-80 I had.  To this day I cringe when I do a 
>first boot even thugh I have moden tools and usually 
>boot from EPROM instead.  Such is memory of the process.

 You always wonder if the program you just toggled in
is going the wipe out all the work you previously
entered. Or worse, wipe out a CP/M distribution disk.

>
>It wasn't until around late '77 (same time I got my NS*)
>that I started seeing turnkey machines as the norm.  

 As you state, normal turnkey used boot ROMs/EPROMs. One
might consider my setup to be turnkey but it isn't a
normal turnkey. There is no boot ROM/EPROM. It just uses
the normal reset of the controller without main CPU
interaction. It is not fully automatic since I do need
to hit the reset and wait for the disk to complete before
enabling the computer to go. Almost full turnkey.
Dwight

>
>
>Allison
>
>

PS As Joe mentioned, I did go off subject and should
have started another thread. For that I apologize.