Advanced features for motor control

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Advanced features for motor control

4.1

Signal generation

The STM32 timer can output two complementary signals and manage the switching-off and

the switching-on instants of the outputs.

The complementary signals OCx and OCxN are activated by a combination of several

control bits: the CCxE and CCxNE and the MOE, OISx, OISxN, OSSI and OSSR bits.

The main output enable (MOE) bit is reset as soon as a break input is active. It is set by

software or automatically, depending on the automatic output enable (AOE) bit. When this

bit (MOE) is reset, the OCx and OCxN outputs are disabled or forced to idle state (OISx

OISxN), depending on whether the OSSI bit is set or not.

Note:

The MOE bit is valid only on the channels that are configured in output.

The Off-state selection for Run mode (OSSR) bit is used when MOE=1 on channels that

have a complementary output configured as outputs. When this bit is set, OCx and OCxN

outputs are enabled with their inactive level as soon as CCxE=1 or CCxNE=1. The output is

still controlled by the timer.

The Off-state selection for Idle mode (OSSI) bit is used when MOE=0 due to a break event

or by a software write, on channels configured as outputs. When this bit is set, OCx and

OCxN outputs are first forced with their inactive level, then forced to their idle level after the

dead time. The timer maintains its control over the output.

Table 4 explains the possible configurations of the advanced timer.