p87c591vfb NXP Semiconductors, p87c591vfb Datasheet - Page 40

• Manufacturer Part Number: p87c591vfb
• Description: Single-chip 8-bit Microcontroller With Can Controller
• Manufacturer: NXP Semiconductors

Philips Semiconductors
12.5.7
The RIL register is used to define the receive interrupt level for the RXFIFO. A receive interrupt is generated if the number
of valid CAN message bytes in the RXFIFO exceeds the level specified in this register. Note that receive interrupts are
only generated if complete messages have been received. If RIL is set to 00 the PeliCAN functions like the receive
interrupt behaviour of the SJA1000.
Table 18 Bit interpretation of the Rx Interrupt Level (RIL)
12.5.8
The contents of the Bus Timing Register 0 defines the values of the Baud Rate Prescaler (BRP) and the Synchronization
Jump Width (SJW). This register can be accessed (read/write) if the Reset Mode is active. In Operating Mode, this
register is read only.
Table 19 Bus Timing Register 0 (BTR0) (CAN address 6)
12.5.8.1
The period of the CAN system clock t
is calculated using the following equation:
12.5.8.2
To compensate for phase shifts between clock oscillators of different bus controllers, any bus controller must
resynchronize on any relevant signal edge of the current transmission. The synchronization jump width defines the
maximum number of clock cycles a bit period may be shortened or lengthened by one resynchronization:
2000 Jul 26
Single-chip 8-bit microcontroller with CAN controller
SJW.1
RIL.7
7
7
CAN ADDR. 5
RX I
B
US
Baud Rate Prescaler (BRP)
Synchronization Jump Width (SJW)
NTERRUPT
T
IMING
SJW.0
t scl
RIL.6
6
R
6
EGISTER
L
=
EVEL
t CLK
(RIL)
0 (BTR0)
BRP.5
32 BRP.5
t CLK
RIL.5
5
scl
5
is programmable and determines the individual bit timing. The CAN system clock
=
t SJW
time period of the C´s system clock
+
16 BRP.4
=
BRP.4
RIL.4
t scl
4
4
2 SJW.1
+
40
8 BRP.3
RX INTERRUPT LEVEL (RIL)
BRP.3
RIL.3
3
+
3
SJW.0
+
4 BRP.2
+
1
BRP.2
=
+
RIL.2
-------------- -
f CLK
2 BRP.1
2
2
1
+
BRP.0
BRP.1
Preliminary Specification
RIL.1
1
1
+
1
P8xC591
BRP.0
RIL.0
0
0