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+--- Thread: Any Time Module experts out there? (/thread-8738.html)
Any Time Module experts out there? - Monte Dalrymple - 07-28-2017 05:24 AM
Subject says it all. Anyone familiar with the working of the software in the Time
Module? Especially the "Timer ROM I/O Buffer" in user memory. Things like how it's
created, what is the structure. It's extremely painful tracing code via a logic analyzer,
so I'm looking for a shortcut.
RE: Any Time Module experts out there? - Ángel Martin - 07-28-2017 08:14 AM
I'm not an expert but here's some observations poking about the buffer contents, after creating alarms using XYZALM
1. the buffer header (bottom of the buffer memory) has the id# (AA corresponding to buffer #10) in digits <13:12>,and the buffer size in digits <11:10>
2. new alarms are added to the bottom of buffer, i.e right below the header - thus pushing up (in memory) the existing ones.
3. each alarm entry uses a variable number of registers (from 1 to 3 I believe), depending on the supplied information (message, repeat interval, date and time). I'm not sure where's the information on how many registers the entry uses, can't identify the digit pattern so far
4. Looks like the first register contains both the date and time, the second has the repeats or the message if only one of those is provided, and the third the message to display when both repeats and message are provided. The formats are not evident, must use either Julian dates or number of days after a reference date... I vaguely remember reading about that.
5. the last register (top of buffer memory) is always "F000000000000"
Hope this helps to get you started...