Notes On Using Nvr Interface - Fujitsu 8FX Hardware Manual

MB95630H Series
27.5

Notes on Using NVR Interface

This section provides notes on using the NVR interface.
■ Note on Changing Main CR Frequency
Please note that the NVR interface does not program a modified value to the NVR Flash area.
To modify the CRTH, CRTL and CRTDA registers, program their new values to the NVR
Flash with the Flash writer.
■ Note on Flash Erase and Trimming Value
1. A Flash erase operation will erase all NVR data.
The Flash writer carries out the following procedure to keep original system settings.
(1) Make a backup of data in CRTH:CRTH[4:0], CRTL:CRTL[4:0] and CRTDA:CRTDA[4:0].
(2) Erase the Flash.
(3) Restore all data in CRTH:CRTH[4:0], CRTL:CRTL[4:0] and CRTDA:CRTDA[4:0] to
the NVR Flash area.
If there is new data in CRTH:CRTH[4:0], CRTL:CRTL[4:0] and CRTDA:CRTDA[4:0], the
Flash writer will program the new data to the NVR Flash area.
2. The trimming value has been preset before this device is shipped. If the preset trimming
value is modified after the device has been shipped, Fujitsu Semiconductor does not warrant
proper operation of the device with respect to use based on the modified trimming value.
3. If the Flash operation is performed by the user program code, restore the original trimming
data to the NVR Flash area by the user program code. Otherwise, the trimming value, which
has been preset before this device is shipped, is erased by the Flash erase operation.
MN702-00009-2v0-E
CHAPTER 27 NON-VOLATILE REGISTER (NVR) INTERFACE
FUJITSU SEMICONDUCTOR LIMITED
27.5 Notes on Using NVR Interface
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