beautypg.com

11 sw, Figure 5. serial control port - i, C slave mode – Cirrus Logic CS49DV8C User Manual

Page 16

background image

16

Copyright 2008 Cirrus Logic, Inc.

DS868PP2

CS49DV8C Data Sheet
32-bit Audio DSP Family

5.11 Switching Characteristics — Serial Control Port - I

2

C Slave Mode

Figure 5. Serial Control Port - I

2

C Slave Mode Timing

Parameter

Symbol

Min

Typical

Max

Units

SCP_CLK frequency

1

1. The specification f

iicck

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.

f

iicck

-

400

kHz

SCP_CLK low time

t

iicckl

1.25

-

µs

SCP_CLK high time

t

iicckh

1.25

-

µs

SCP_SCK rising to SCP_SDA rising or falling for
START or STOP condition

t

iicckcmd

1.25

µs

START condition to SCP_CLK falling

t

iicstscl

1.25

-

µs

SCP_CLK falling to STOP condition

t

iicstp

2.5

-

µs

Bus free time between STOP and START conditions

t

iicbft

3

-

µs

Setup time SCP_SDA input valid to SCP_CLK rising

t

iicsu

100

ns

Hold time SCP_SDA input after SCP_CLK falling

t

iich

20

-

ns

SCP_CLK low to SCP_SDA out valid

t

iicdov

-

18

ns

SCP_CLK falling to SCP_IRQ rising

t

iicirqh

-

3

*

DCLKP + 40

ns

NAK condition to SCP_IRQ low

t

iicirql

3

*

DCLKP + 20

ns

SCP_CLK rising to SCB_BSY low

t

iicbsyl

-

3

*

DCLKP + 20

ns

SCP_BSY

SCP_CLK

SCP_SDA

SCP_IRQ

0

1

6

7

8

0

1

7

t

iicckl

t

iicckh

t

iicsu

t

iich

A6

A0

R/W

ACK

LSB

t

iicirqh

t

iicirql

8

ACK

MSB

t

iicstp

6

t

iiccbsyl

t

iicdov

t

iicbft

t

iicstscl

t

iicckcmd

f

iicck

t

iicckcmd

t

iicf

t

iicr