W311_05 Datasheet, PDF (9/19 Pages) Cypress Semiconductor – FTG for VIA™ Pro-266 DDR Chipset

W311
Byte 11: Recovery Frequency N - Value Register
Bit
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Name
ROCV_FREQ_N7
ROCV_FREQ_N6
ROCV_FREQ_N5
ROCV_FREQ_N4
ROCV_FREQ_N3
ROCV_FREQ_N2
ROCV_FREQ_N1
ROCV_FREQ_N0
Default
Description
0 If ROCV_FREQ_SEL is set, W311 will use the values programmed in
0
ROCV_FREQ_N[7:0] and ROCV_FREQ_M[6:0] to determine the recovery
CPU output frequency.when a Watchdog Timer time-out occurs.
0 The setting of FS_Override bit determines the frequency ratio for CPU, SDRAM,
0
AGP and SDRAM. When it is cleared, W311 will use the same frequency ratio
stated in the Latched FS[4:0] register. When it is set, W311 will use the
0 frequency ratio stated in the SEL[4:0] register.
0
W312 supports programmable CPU frequency ranging from 50 MHz to 248
MHz.
0 W311 will change the output frequency whenever there is an update to either
0
ROCV_FREQ_N[7:0] and ROCV_FREQ_M[6:0]. Therefore, it is recommended
to use Word or Block write to update both registers within the same SMBus bus
operation.
Byte 12: Recovery Frequency M- Value Register
Bit
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Name
ROCV_FREQ_SEL
ROCV_FREQ_M6
ROCV_FREQ_M5
ROCV_FREQ_M4
ROCV_FREQ_M3
ROCV_FREQ_M2
ROCV_FREQ_M1
ROCV_FREQ_M0
Default
0
0
0
0
0
0
0
0
Pin Description
ROCV_FREQ_SEL determines the source of the recover frequency when a
Watchdog Timer time-out occurs. The clock generator will automatically
switch to the recovery CPU frequency based on the selection on
ROCV_FREQ_SEL.
0 = From latched FS[4:0]
1 = From the settings of ROCV_FREQ_N[7:0] & ROCV_FREQ_M[6:0]
If ROCV_FREQ_SEL is set, W311 will use the values programmed in
ROCV_FREQ_N[7:0] and ROCV_FREQ_M[6:0] to determine the recovery
CPU output frequency.when a Watchdog Timer time-out occurs.The setting
of FS_Override bit determines the frequency ratio for CPU, SDRAM, AGP and
SDRAM. When it is cleared, W311 will use the same frequency ratio stated in
the Latched FS[4:0] register. When it is set, W311 will use the frequency ratio
stated in the SEL[4:0] register. W311 supports programmable CPU frequency
ranging from 50 MHz to 248 MHz.
Byte 13: Programmable Frequency Select N-Value Register
Bit
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Name
CPU_FSEL_N7
CPU_FSEL_N6
CPU_FSEL_N5
CPU_FSEL_N4
CPU_FSEL_N3
CPU_FSEL_N2
CPU_FSEL_N1
CPU_FSEL_N0
Default
0
0
0
0
0
0
0
0
Pin Description
If Prog_Freq_EN is set, W311 will use the values programmed in
CPU_FSEL_N[7:0] and CPU_FSEL_M[6:0] to determine the CPU output
frequency. The new frequency will start to load whenever CPU_FSELM[6:0]
is updated.
The setting of FS_Override bit determines the frequency ratio for CPU,
SDRAM, AGP and SDRAM. When it is cleared, W311 will use the same
frequency ratio stated in the Latched FS[4:0] register. When it is set, W311
will use the frequency ratio stated in the SEL[4:0] register. W311 supports
programmable CPU frequency ranging from 50 MHz to 248 MHz.
Document #: 38-07703 Rev. **
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