Cypress FM4 Series - High-Speed CR Oscillation Register Write-Protect Register (MCR_RLR)

CHAPTER 2-3: High-Speed CR Trimming
128 FM4 Peripheral Manual, Doc. No. 002-04856 Rev. *E
5.4 High-Speed CR Oscillation Register Write-Protect Register (MCR_RLR)
The MCR_RLR register controls the write-protect state of the frequency trimming register
(MCR_FTRM)/high-speed CR oscillation temperature trimming register (MCR_TTRM).
Register configuration
bit
31
16
Field
TRMLCK[31:16]
Attribute
R/W
Initial value
0x0000
bit
15
0
Field
TRMLCK[15:0]
Attribute
R/W
Initial value
0x0001
Register functions
[bit31:0] TRMLCK[31:0] : Register write-protect bits
bit31:0
Description
When read
When 0x00000000 is read, the MCR_FTRM/MCR_TTRM register is currently
unlocked.
When 0x00000001 is read, the MCR_FTRM/MCR_TTRM register is currently locked.
Writing a value other
than 0x1ACCE554
Locks the MCR_FTRM/MCR_TTRM register
Writing 0x1ACCE554
Unlocks the MCR_FTRM/MCR_TTRM register
Note:
− This register is not initialized by software reset.