Integrator™/CM10200E and CM10220E User Guide 4.3.6. Lock Register, CM

4.3.6. Lock Register, CM_LOCK

The Core Module Lock Register, CM_LOCK, at 0x10000014 controls access to the following registers to enable them to be locked and unlocked:

Oscillator Register, CM_OSC
Auxiliary Oscillator Register, CM_AUXOSC
Voltage Configuration Registers, CM_VOLTAGE_CTL0-3
Initialization Register, CM_INIT.

This mechanism prevents the registers from being overwritten accidently. Figure 4.7 shows the bit assignment of the register.

Figure 4.7. Lock Register, CM_LOCK

Table 4.9 describes the Core Module Lock Register bit assignment.

Table 4.9. Lock Register, CM_LOCK bit assignment

Bits	Name	Access	Function
[31:17]	Reserved	Use read-modify-write to preserve value.
[16]	LOCKED	Read	This bit indicates if the CM_OSC, CM_AUXOSC, CM_INIT, and CM_VOLTAGE_CTL0-3 Registers are locked or unlocked: 0 = unlocked 1 = locked.
[15:0]	LOCKVAL	Read/write	Write the value `0xA05F` to this register to enable write accesses to the CM_OSC, CM_AUXOSC, CM_INIT, and CM_VOLTAGE_CTL0-3 Registers. Write any other value to this register to lock the CM_OSC register.

Bits

Name

Access

Function

[31:17]

Reserved

Use read-modify-write to preserve value.

[16]

LOCKED

Read

This bit indicates if the CM_OSC, CM_AUXOSC, CM_INIT, and CM_VOLTAGE_CTL0-3 Registers are locked or unlocked:

0 = unlocked

1 = locked.

[15:0]

LOCKVAL

Read/write

Write the value 0xA05F to this register to enable write accesses to the CM_OSC, CM_AUXOSC, CM_INIT, and CM_VOLTAGE_CTL0-3 Registers. Write any other value to this register to lock the CM_OSC register.

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