Cypress S6J3200 Series, Руководство пользователя

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CHAPTER 16:Stepper Motor Controller
S6J3200 Series Hardware Manual Document Number: 002-04852 Rev. *G 381
3.3.
Synchronization System of Stepper Motor Controller
The Stepper Motor Controller contains a dedicated system developed to enable synchronization of
PWM1 and PWM2 Pulse Generators, as well as Stepper Motor Controller output pin selection. The
synchronization system is controlled by the PWM Selection Register Output Update bit (PWS.BS). Until
the Output Update bit (PWS.BS) is set to "1", changes made to the PWM Compare Registers (PWC1,
PWC2) and the PWM Selection Register (PWS) are not reflected on the output. Configuring the Stepper
Motor Controller output pin selection and setting the Output Update bit (PWS.BS) simultaneously (in the
same software access) is allowed.
When the Output Update bit (PWS.BS) is set to "1"by software, and the end of current PWM cycle is
detected, PWM Pulse Generator and motor drive selection logic will load values of the corresponding
registers. The Output Update bit (PWS.BS) is automatically cleared to "0" at the beginning of the next
PWM cycle.
If the Output Update bit (PWS.BS) is equal to "1"and the software access is initiated to set this bit to "1"at
the beginning of the PWM cycle (at the same time when an automatic clear of Output Update bit
(PWS.BS) is issued), the Output Update bit (PWS.BS) will retain the value "1"(i.e. no change is made to
the PWS.BS bit) and the automatic clearing is canceled for this PWM cycle.
The following scenario is shown on Figure 3-3:
1.
Automatic clear of the Output Update bit (PWS.BS): load operation is executed and reflected on the
output.
Figure 3-3 Load Timing of PWM Compare Register and PWM Selection Register