Table 131. Smbus Timeout Specifications - ST STM32F413 Reference Manual

Fast-mode Plus Inter-integrated circuit (FMPI2C) interface
Timeouts
This peripheral embeds hardware timers in order to be compliant with the 3 timeouts defined
in SMBus specification version 2.0.
.
Symbol
t
TIMEOUT
t
LOW:SEXT
t
LOW:MEXT
1. t
LOW:SEXT
from the initial START to the STOP. It is possible that, another slave device or the master will also extend
the clock causing the combined clock low extend time to be greater than t
parameter is measured with the slave device as the sole target of a full-speed master.
2. t
LOW:MEXT
message as defined from START-to-ACK, ACK-to-ACK, or ACK-to-STOP. It is possible that a slave device
or another master will also extend the clock causing the combined clock low time to be greater than
t
LOW:MEXT
target of the master.
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Table 131. SMBus timeout specifications

Detect clock low timeout
(1)
Cumulative clock low extend time (slave device)
(2)
Cumulative clock low extend time (master device)
is the cumulative time a given slave device is allowed to extend the clock cycles in one message
is the cumulative time a master device is allowed to extend its clock cycles within each byte of a
on a given byte. Therefore, this parameter is measured with a full speed slave device as the sole
Figure 265. Timeout intervals for t
DocID029473 Rev 3
Parameter
LOW:SEXT
RM0430
Limits
Min Max
25 35
- 25
- 10
. Therefore, this
LOW:SEXT
, t .
LOW:MEXT
Unit
ms
ms
ms