9 swi, Confidenti a l dra ft d elphi – Cirrus Logic CS48DV2B User Manual
Page 14
CS48DV2B Data Sheet
32-bit Audio DSP for Dedicated Dolby Volume and Audistry by Dolby
14
Copyright 2009 Cirrus Logic
DS875F2
CONFIDENTIAL
CONFIDENTI
A
L
DRA
FT
D
ELPHI
5.9 Switching Characteristics — Serial Control Port - SPI Slave Mode
.
Figure 3. Serial Control Port - SPI Slave Mode Timing
Parameter
Symbol
Min
Typical
Max
Units
SCP_CLK frequency
1
1. The specification f
spisck
indicates the maximum speed of the hardware. The system designer should be aware that the actual
maximum speed of the communication port may be limited by the firmware application. Flow control using the SCP_BSY pin
should be implemented to prevent overflow of the input data buffer. At boot the maximum speed is F
xtal
/3.
f
spisck
-
25
MHz
SCP_CS falling to SCP_CLK rising
t
spicss
24
-
ns
SCP_CLK low time
t
spickl
20
-
ns
SCP_CLK high time
t
spickh
20
-
ns
Setup time SCP_MOSI input
t
spidsu
5
-
ns
Hold time SCP_MOSI input
t
spidh
5
-
ns
SCP_CLK low to SCP_MISO output valid
t
spidov
-
11
ns
SCP_CLK falling to SCP_IRQ rising
t
spiirqh
-
20
ns
SCP_CS rising to SCP_IRQ falling
t
spiirql
0
ns
SCP_CLK low to SCP_CS rising
t
spicsh
24
-
ns
SCP_CS rising to SCP_MISO output high-Z
t
spicsdz
-
20
ns
SCP_CLK rising to SCP_BSY falling
t
spicbsyl
-
3
*
DCLKP+20
ns
SCP_BSY
SCP_CS
SCP_CLK
SCP_MOSI
SCP_MISO
SCP_IRQ
0
1
2
6
7
0
5
6
7
t
spicss
t
spickl
t
spickh
t
spidsu
t
spidh
t
spidov
A6
A5
A0
R/W
MSB
LSB
MSB
LSB
t
spicsh
t
spibsyl
t
spiirql
t
spiirqh
f
spisck
t
spicsdz