TC1796
Peripheral Units (Vol. 2 of 2)
Controller Area Network (MultiCAN) Controller
User’s Manual
22-143
V2.0, 2007-07
MultiCAN, V2.0
automatically cleared when the time mark is reached). As a result, this interrupt
indicates that a (no) message has been sent /received in the time window between
the time marks n-1 and n.
•
Receive Control Entry:
Valid receive control information (CHEN, RCEMSGNR) controls the storage of a
message in the time window between the time marks n-1 and n.
•
Arbitration Entry:
Valid arbitration information (ARBM) determines the behavior of the time window
starting with the time mark n.
•
Transmit Control Entry:
Valid transmit control information (TREN, ALTMSG, TCEMSGNR) defines a
message to be transmitted after the time mark n. The transmission start is possible
while the transmit enable window is active for an exclusive window or for a short
(single) arbitration window or for the end of a merged arbitration window. For a
merged (long) arbitration window, the transmission can start during the complete
time window.
•
Reference Message Entry:
not used in this time window
•
Basic Cycle End Entry:
not used in this time window
The TMV value collected after time mark n-1 will become the new compare value for the
time mark n.
The value of CYCTMR.CSM equals the time mark number of the last time mark reached
(CSM = n after time mark n has been reached). The value of CYCTMR.BCC is number
of the current basic cycle. This information is needed to correctly set up the scheduler
entries (bit fields CYCLE, MCYCLE) and the message objects (bit fields CYCLE,
MCYCLE, COLUMN, MCOLUMN).
22.6.4.2 Instructions at the End of a Basic Cycle
The collection of instructions for the last time window of a basic cycle starts when the
time mark before is reached and stops when the entry TME2 is found. Handling of the
entries collected during the last time window of a basic cycle:
•
Time Mark Entry:
After a valid BCE has been read, the first time mark TME1 is read and its value is
defining the compare value for the time mark 1 (first time mark after the reference
message = start of a new basic cycle).
•
Interrupt Entry:
Valid interrupt information (INP+ 4 enable bits) collected during the last time window
of a basic cycle can generate an interrupt when the time mark 1 is reached,
depending on the flags RECF and TRAF (they are automatically cleared when the
time mark is reached). These flags do not apply to the reference message (the