[Info-vax] Calling $CREPRC in COBOL

[Simon Clubley]

On 2022-06-14, Single Stage to Orbit <alex.buell at munted.eu> wrote:
> On Mon, 2022-06-13 at 22:54 -0500, Dennis Boone wrote:
>>  > Using COBOL to interface to VMS has been a serious eye-opener for
>> me in
>>  > reading this thread.  I guess no-one is going to be doing even a
>> bare
>>  > metal LED blinker in COBOL any time soon...  :-)
>> 
>> Never underestimate the chance that some weirdo may combine some COMP
>> data, the REVERSE verb, and some overlay moves.  I mean, there's
>> http://www.coboloncogs.org/ so...
>> 
>> /me ponders how to nmost obscurely get GPIO on a vax or itanic.
>
> Raspberry Pi, using OpenCOBOL. See the 9th post on
> https://forums.raspberrypi.com/viewtopic.php?t=139325 for the gory
> details :-D
>

That is _NOT_ bare metal however. :-)

Bare metal is where your code is running directly on the hardware without
any operating system underneath it and where your COBOL program is directly
reading and writing from/to device registers and directly receiving device
interrupts.

You are allowed to use an assembly language dispatcher for the interrupt
handler that then calls your COBOL interrupt handler but that means your
COBOL code still needs to be able to work in interrupt context for the
device in question.

Simon.

-- 
Simon Clubley, clubley at remove_me.eisner.decus.org-Earth.UFP
Walking destinations on a map are further away than they appear.