ST72561AR7 STMicroelectronics, ST72561AR7 Datasheet - Page 263

• Manufacturer Part Number: ST72561AR7
• Description: 8-bit MCU
• Manufacturer: STMicroelectronics

Specifications of ST72561AR7

• Hdflash Endurance: 100 cycles, data retention 40 years at 85°C
• 5 Power Saving Modes: Halt, Auto Wake Up From Halt, Active Halt, Wait and Slow

IMPORTANT NOTES (Cont’d)
Occurrence
The occurrence of the problem is random and pro-
portional to the baud rate. With a transmit frequen-
cy
SCIBRR = 0xC9), the wrong break duration occur-
rence is around 1%.
Analysis
The LIN protocol specifies a minimum of 13 bits for
the break duration, but there is no maximum value.
Nevertheless, the maximum length of the header
is specified as (14+10+10+1) x 1.4 = 49 bits. This
is composed of:
- the synch break field (14 bits)
- the synch field (10 bits)
- the identifier field (10 bits)
Every LIN frame starts with a break character.
Adding an idle character increases the length of
each header by 10 bits. When the problem occurs,
the header length is increased by 11 bits and be-
comes ((14+11)+10+10+1) = 45 bits.
To conclude, the problem is not always critical for
LIN communication if the software keeps the time
between the sync field and the ID smaller than 4
bits, that is, 208µs at 19200 baud.
of
19200
baud
(f
CPU
= 8
MHz
and
The workaround is the same as for SCI mode but
considering the low probability of occurrence (1%),
it may be better to keep the break generation se-
quence as it is.
16.2.2 16-bit and 8-bit Timer PWM Mode
In PWM mode, the first PWM pulse is missed after
writing the value FFFCh in the OC1R or OC2R
register.
16.3 ROM DEVICES ONLY
16.3.1 16-bit Timer PWM Mode Buffering
Feature Change
In all devices, the frequency and period of the
PWM signal are controlled by comparing the coun-
ter with a 16-bit buffer updated by the OCiHR and
OCiLR registers. In ROM devices, contrary to the
description in
output compare function is not inhibited after a
write instruction to the OCiHR register. Instead the
buffer update at the end of the PWM period is in-
hibited until OCiLR is written. This improved buffer
handling is fully compatible with applications writ-
ten for Flash devices.
Section 10.5.3.5 on page
ST72561
103, the
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