CY28341-3
Byte 7: Dial-a-Frequency Control Register N
Bit
7
6
5
4
3
2
1
0
@Pup
0
0
0
0
0
0
0
0
Pin#
Name
Reserved
N6, MSB
N5
N4
N3
N2
N3
N0, LSB
Description
Reserved for device function test.
These bits are for programming the PLL's internal N register. This access
allows the user to modify the CPU frequency at very high resolution
(accuracy). All other synchronous clocks (clocks that are generated from
the same PLL, such as PCI) remain at their existing ratios relative to the
CPU clock.
Byte 8: Silicon Signature Register (all bits are read-only)
Bit
7
6
5
4
3
2
1
0
@Pup
0
0
0
0
1
0
0
0
Pin#
Name
Revision_ID3
Revision_ID2
Revision_ID1
Revision_ID0
Vendor_ID3
Vendor_ID2
Vendor_ID1
Vendor_ID0
Revision ID bit [3]
Revision ID bit [2]
Revision ID bit [1]
Revision ID bit [0]
Cypress’s Vendor ID bit [3].
Cypress’s Vendor ID bit [2].
Cypress’s Vendor ID bit [1].
Cypress’s Vendor ID bit [0].
Description
Byte9: Dial-A-Frequency Control Register R
Bit
7
6
5
4
3
2
1
0
@Pup
0
0
0
0
0
0
0
0
Pin#
Name
Reserved
R5, MSB
R4
R3
R2
R1
R0
DAF_ENB
R and N register mux selection. 0 = R and N values come from the ROM.
1 = data is load from DAF (SMBus) registers.
Table 9. Spread Spectrum Table
Mode
0
0
0
0
FS(4:0)
XXXXX
P
96016000
1
1
1
1
SST1
0
0
1
1
0
0
1
1
SST0
0
1
0
1
0
1
0
1
% Spread
–1.5%
–1.0%
–0.7%
–0.5%
±0.75%
±0.5%
±0.35%
±0.25%
Reserved
These bits are for programming the PLL's internal R register. This access
allows the user to modify the CPU frequency at very high resolution
(accuracy). All other synchronous clocks (clocks that are generated from the
same PLL, such as PCI) remain at their existing ratios relative to the CPU
clock.
Description
Dial-A-Frequency Feature
SMBus Dial-a-Frequency feature is available in this device via
Byte7 and Byte9.
P is a PLL constant that depends on the frequency selection
prior to accessing the Dial-a-Frequency feature.
Table 8.
Spread Spectrum Clock Generation (SSCG)
Spread Spectrum is enabled/disabled via SMBus register
Byte 1, Bit 7.
Rev 1.0, November 21, 2006
Page 8 of 19
SPECTRALINEAR [ SPECTRALINEAR INC ]
