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INTERNAL
If the Internal function is enabled, the CANTX
and CANRX pins of the CAN module are inter-
nally connected to each other. This feature
can be used in conjunction with the LOOP-
BACK mode. This means that the CAN mod-
ule can receive its own sent messages
without connecting an external transceiver
chip to the CANTX and CANRX pins; it allows
software to run real stand-alone tests without
any peripheral devices.
0 – Normal mode.
1 – Internal mode.
DIAGEN
The Diagnostic Enable bit globally enables or
disables the special diagnostic features of the
CAN module. This includes the following func-
tions:
•
LO (Listen Only).
•
IGNACK (Ignore Acknowledge).
•
LOOPBACK (Loopback).
•
INTERNAL (Internal Loopback).
•
Write access to hidden receive buffer.
0 – Normal mode.
1 – Diagnostic features enabled.
EIT
The Error Interrupt Type bit configures when
the Error Interrupt Pending Bit (CIPND.EIP-
ND) is set and an error interrupt is generated
if enabled by the Error Interrupt Enable
(CIEN.EIEN).
0 – The EIPND bit is set on every error on the
CAN bus.
1 – The EIPND bit is set only if the error state
(CSTPND.NS) changes as a result of in-
crementing either the receive or transmit
error counter.
19.10.7 CAN Timing Register (CTIM)
The Can Timing Register (CTIM) defines the configuration
of the Bit Time Logic (BTL).
15
9
PSC
PSC
The Prescaler Configuration field specifies
the CAN prescaler. The settings are shown in
Table 57
Table 57 CAN Prescaler Settings
PSC6:0
000000
000001
000010
000011
000100
1111101
1111110
1111111
SJW
The Synchronization Jump Width field speci-
fies the Synchronization Jump Width, which
can be programmed between 1 and 4 time
quanta (see Table 58).
SJW
00
01
10
11
Note: The settings of SJW must be configured to be small-
er or equal to TSEG1 and TSEG2
135
8
7
6
3
2
SJW
TSEG1
TSEG2
0
R/W
Prescaler
2
3
4
5
6
:
:
127
128
128
Table 58 SJW Settings
Synchronization Jump
Width (SJW)
1 time quantum
2 time quanta
3 time quanta
4 time quanta
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