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XC161 Derivatives
Peripheral Units (Vol. 2 of 2)
TwinCAN Module
User’s Manual
21-42
V2.2, 2004-01
TwinCAN_X1, V2.1
Figure 21-23 CPU Handling of Message Objects with Direction = Transmit
MCA05493
Want to Send
?
yes
Update Message
?
yes
no
no
TXRQ := ‘10’
CPUUPD := ‘01’
MSGVAL = ‘01’
INTPND := ‘01’
RMTPND := ‘01’
TXRQ := ‘01’
NEWDAT := ‘01’
DIR := ‘1’ (transmit object)
Identifier := (application specific)
XTD := (application specific)
TXIE := (application specific)
RXIE := (application specific)
CPUUPD := ‘10’
MSGVAL := ‘10’
Write / Calculate Message Contents
(all bits written with reset values)
Power Up
Message Initialization
Update : Start
Update : End
CPUUPD := ‘10’
NEWDAT := ‘10’
Update
‘01’ : Reset
‘10’ : Set