NEC uPD72257, Preliminary User'S Manual

Page: 99 / 343

Refer also to the description of the SYSBOOTMODE, SYSPLLCTRL and
SYSCLKCTRL registers.
MODE7 SDRAM enable
MODE7 is used to enable the external SDRAM interface after RESET release.
MODE7 is stored in SYSBOOTMODE.BOOTMODE7 and is used to set the reset
value of the SYSCLKCTRL.SDREN bit.
Refer also to the description of the SYSBOOTMODE and SYSCLKCTRL registers.
MODE8 Ravin device type selection
MODE8 is stored in SYSBOOTMODE.BOOTMODE8 and has to be set according
to the graphics controller type:
• MODE8 = 0 SYSBOOTMODE.BOOTMODE8 = 0: Ravin-L
• MODE8 = 1 SYSBOOTMODE.BOOTMODE8 = 1: Ravin-M
Refer also to the description of the SYSBOOTMODE register.
MODE9 Internal RAM enable (Ravin-L only)
MODE9 is used to enable the clock for the internal RAM after RESET release.
MODE9 is stored in SYSBOOTMODE.BOOTMODE9 and is used to set the reset
value of the SYSCLKCTRL.IRAMCLKEN bit.
Refer also to the description of the SYSBOOTMODE and SYSCLKCTRL registers.
MODE10 User defined configurations
The level of MODE10 is only stored in SYSBOOTMODE.BOOTMODE10 after
RESET release.
It is not used for any predefined purposes and can be used by the user’s
application to perform application specific initializations by software.
Refer also to the description of the SYSBOOTMODE register.
System Controller Chapter 4
Preliminary User's Manual S19203EE1V3UM00
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