Editing SmartBox OS (section)

==== OS_CALLOS 1: Claim a block of JobCodes ====

{|class="calltable"
|Entry||
* A = 1
* X = number of JobCodes required
* Y, c, z = undefined
|-
|Exit||
* A = 0
* X = base JobCode, if 0, no big enough block available
* Y = Job ID number, 0 if no big enough block
* c = set if no big enough block
* z is preserved
|-
|Note||
This call claims JobCodes codes from the JobCode list.  JobCodes
are in the range 0 to 255, 0 is special and is the JobCall "Blank".  All the
OS ones are spaced out but an "application" can claim a block of JobCodes,
usually just the 1 call.  If there is not a contigous block big enough then
no JobCodes are allocated and the appropiate result is returned.  The Job ID
is from 0 to 255, 0 is unallocated, 1 is the OS calls, the rest are external
applications, each successful call increments the Job ID returned, meaning a
maximum of 255 successful calls (not important as their is not that many
free calls available !), the Job ID can be used to check whether a JobCall
request is yours.
|}