AD Controls Department » Front-end Group » Infrastructure » MOOC Framework

When Kevin Cahill defined the GETS32 and SETS32 protocols, he inexplicably used the same format for both headers. The Erlang-based front-ends took advantage of that fact by supporting the FTD field in the SETS32 header. MOOC should also do this.

The semantics:

• SETS32 behaves exactly like SETDAT when the FTD field is set to "i" (i.e. once immediate.)
• If the FTD is a clock or state event, the SETS32 handler waits for the event to occur before applying the setting and returning a status.
• If the FTD is periodic, the handler waits for the next occurrence (i.e. a delay) before applying the setting and returning a status.
• If the SETS32 request asks for multiple replies, then the setting is applied each time the event fires (and status is returned each time.)
• The client can cancel the request to end the multiple replies or prevent a one-time setting, if the cancel happens before the event fires.