Atmel ARM-Based Evaluation Kit for SAM4S16C, 32-Bit ARM® Cortex® Microcontroller ATSAM4S-WPIR-RD ATSAM4S-WPIR-RD Hoja De Datos

953

SAM4S Series [DATASHEET]

Atmel-11100G-ATARM-SAM4S-Datasheet_27-May-14

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Register group 4:

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Register group 5:

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There are two types of Write Protection:

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SW Write Protect—can be enabled or disabled by software

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HW Write Protect—can be enabled by software but only disabled by a hardware reset of the PWM controller

Both types of Write Protect can be applied independently to a particular register group by means of the WPCMD 

and WPRGx fields in the PWM_WPCR. If at least one Write Protect is active, the register group is write-protected. 

The value of field WPCMD defines the action to be performed:

0: disables SW Write Protect of the register groups of which the bit WPRGx is at ‘1’
1: enables SW Write Protect of the register groups of which the bit WPRGx is at ‘1’
2: enables HW Write Protect of the register groups of which the bit WPRGx is at ‘1’

At any time, the user can determine which Write Protect is active in which register group by the fields WPSWS and 

WPHWS in the 

 (PWM_WPSR).

If a write access in a write-protected register is detected, then the WPVS flag in the PWM_WPSR is set and the 

field WPVSRC indicates in which register the write access has been attempted, through its address offset without 

the two LSBs.
The WPVS and WPVSRC fields are automatically cleared after reading the PWM_WPSR.