cp3bt13 National Semiconductor Corporation, cp3bt13 Datasheet - Page 101

• Manufacturer Part Number: cp3bt13
• Description: Cp3bt13 Reprogrammable Connectivity Processor With Bluetooth-r And Can Interfaces
• Manufacturer: National Semiconductor Corporation

INTERNAL
DIAGEN
EIT
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.
The Diagnostic Enable bit globally enables or
disables the special diagnostic features of the
CAN module. This includes the following func-
tions:
•
•
•
•
•
0 – Normal mode.
1 – Diagnostic features enabled.
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
1 – The EIPND bit is set only if the error state
CAN bus.
(CSTPND.NS) changes as a result of in-
crementing either the receive or transmit
error counter.
LO (Listen Only).
IGNACK (Ignore Acknowledge).
LOOPBACK (Loopback).
INTERNAL (Internal Loopback).
Write access to hidden receive buffer.
101
16.10.7 CAN Timing Register (CTIM)
The Can Timing Register (CTIM) defines the configuration
of the Bit Time Logic (BTL).
PSC
SJW
Note: The settings of SJW must be configured to be small-
er or equal to TSEG1 and TSEG2
15
PSC
The Prescaler Configuration field specifies
the CAN prescaler. The settings are shown in
Table 47
The Synchronization Jump Width field speci-
fies the Synchronization Jump Width, which
can be programmed between 1 and 4 time
quanta (see Table 48).
Table 47 CAN Prescaler Settings
SJW
9
00
01
10
11
1111101
1111110
1111111
PSC6:0
000000
000001
000010
000011
000100
8
Table 48 SJW Settings
SJW
:
R/W
7
0
Synchronization Jump
6
TSEG1
1 time quantum
2 time quanta
3 time quanta
4 time quanta
Width (SJW)
Prescaler
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3
127
128
128
2
3
4
5
6
2
:
TSEG2
0