- SS-HQ1 Application Notes -
Ver.1.0.0 January 7, 2005
67
9.2.4. Clock for Communication with Peripheral ICs
All data are CXD3172AR design values. Communication is LSB-first.
The CASCK frequency varies depending on the frequency of the X’tal connected to the ECK (pin 88). Note that
this frequency is uniquely determined by the DSP firmware and cannot be set by the user.
Table 9.2-3 Serial Communication Clock Frequency
Clock frequency (MHz)
X’tal(ECK)
CASCK
27.00000 0.84
28.37500 0.89
28.63636 0.89
35.46895 1.11
37.87500 1.18
38.13986 1.19
External EVR
Fig 9.2-3 Communication Protocol - External EVR -
A0
A1
A2
A3
D7
D6
D3
D2
D1
D0
S4 or P3
(CSEVR)
CASCK
CASO
A0
<DUMMY>
1st to 4th bit
<ADDRESS>
5th to 8th bit
<DATA>
9th to 16th bit