ST STM32L4 Series, User Manual

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SM CODE UART_SM_0
Detailed implementation
This method must be applied to USART1/2/3/4/5/6/7/8 and LPUART configuration registers.
Detailed information on the implementation of this method can be found in
Section 3.6.14 Extended interrupt and events controller (EXTI) .
Error reporting Refer to NVIC_SM_0
Fault detection time Refer to NVIC_SM_0
Addressed fault model Refer to NVIC_SM_0
Dependency on Device configuration Refer to NVIC_SM_0
Initialization Refer to NVIC_SM_0
Periodicity Refer to NVIC_SM_0
Test for the diagnostic Refer to NVIC_SM_0
Multiple-fault protection Refer to NVIC_SM_0
Recommendations and known limitations Refer to NVIC_SM_0
Table 124. UART_SM_1
SM CODE UART_SM_1
Description Protocol error signals
Ownership ST
Detailed implementation
USART1/2/3/4/5/6/7/8 and LPUART communication module embeds protocol error checks
(like additional parity bit check, overrun, frame error) conceived to detect network-related
abnormal conditions. These mechanisms are able anyway to detect a marginal percentage of
hardware random failures affecting the module itself.
Error signals connected to these checkers are normally handled in a standard communication
software, so the overhead is reduced.
Error reporting Error flag raise and optional interrupt event generation
Fault detection time
Depends on peripheral configuration (for example baud rate). Refer to functional
documentation.
Addressed fault model Permanent/transient
Dependency on Device configuration None
Initialization Depends on implementation
Periodicity Continuous
Test for the diagnostic Not applicable
Multiple-fault protection UART_SM_2: Information redundancy techniques on messages
Recommendations and known limitations
USART1/2/3/4/5/6/7/8 and LPUART communication module allows several different
configurations. The actual composition of communication error checks depends on the
selected configuration.
Enabling related interrupt generation on the detection of errors is highly recommended.
Table 125. UART_SM_2
SM CODE UART_SM_2
Description Information redundancy techniques on messages
Ownership End user
Detailed implementation
This method is implemented by adding to data packets transferred by USART1/2/3/4/5/6/7/8
and LPUART a redundancy check (such as a
CRC check, or similar one) with encoding
capability. The checksum encoding capability must be robust enough to guarantee at least
90% probability of detection for a single bit flip in the data packet.
UM2305
Hardware and software diagnostics
UM2305 - Rev 10
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