MC68HC08AZ16 Datasheet, PDF (382/527 Pages) Motorola, Inc – HCMOS Microcontroller Unit

msCAN08 Controller (msCAN08)
Programmer’s model of control registers
NOTE: The CBTR0 register can only be written if the SFTRES bit in the
MSCAN08 Module Control Register is set.
msCAN08 bus
.
timing register 1
(CBTR1)
CBTR1 R
$xx03 W
RESET
BIT 7
SAMP
0
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
TSEG22 TSEG21 TSEG20 TSEG13 TSEG12 TSEG11 TSEG10
0
0
0
0
0
0
0
Figure 18. Bus timing register 1
SAMP — Sampling
This bit determines the number of samples of the serial bus to be
taken per bit time. If set three samples per bit are taken, the regular
one (sample point) and two preceding samples, using a majority rule.
For higher bit rates SAMP should be cleared, which means that only
one sample will be taken per bit.
1 = Three samples per bit.
0 = One sample per bit.
TSEG22 – TSEG10 — Time segment
Time segments within the bit time fix the number of clock cycles per
bit time, and the location of the sample point.
Time segment 1 (TSEG1) and time segment 2 (TSEG2) are
programmable as shown in Table 8.
The bit time is determined by the oscillator frequency, the baud rate
prescaler, and the number of time quanta (Tq) clock cycles per bit (as
shown above).
NOTE: The CBTR1 register can only be written if the SFTRES bit in the
msCAN08 Module Control Register is set
35-can
MOTOROLA
msCAN08 Controller (msCAN08)
MC68HC08AZ32
381