Figure 18–85, Nxp semiconductors, 2 scenario 2: message lost – NXP Semiconductors LPC24XX UM10237 User Manual
Page 514: Fig 85. normal case, no messages lost, Fig 86. message lost
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User manual
Rev. 04 — 26 August 2009
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NXP Semiconductors
UM10237
Chapter 18: LPC24XX CAN controllers CAN1/2
17.3.2 Scenario 2: Message lost
In this scenario a first FullCAN Message is stored and read out by Software (1
st
Object
write and read). In a second course a second message is stored (2
nd
Object write) but not
read out before a third message gets stored (3
rd
Object write). Since the FullCAN Interrupt
of that Object (IntPndx) is already asserted, the Message Lost Signal gets asserted.
Fig 85. Normal case, no messages lost
01
11
IntPndx
semaphore
bits
look-up
table
access
00
MsgLostx
message
handler
access
ARM
processor
access
read
SEM
read
D2
read
D1
clear
SEM
read
SEM
write
SEM
write
D2
write
D1
Write
ID, SEM
Fig 86. Message lost
01
11
01
11
11
00
1st Object
write
2nd Object
write
1st Object
read
3rd Object
write
IntPndx
semaphore
bits
look-up
table
access
MsgLostx
message
handler
access
ARM
processor
access
read
SEM
read
D2
read
D1
clear
SEM
read
SEM
write
SEM
write
D2
write
D1
write
ID,
SEM
write
SEM
write
D2
write
D1
write
ID,
SEM
write
SEM
write
D2
write
D1
write
ID,
SEM