LSI Logic Confidential
AC Timing
18-29
Copyright © 2001, 2002 by LSI Logic Corporation. All rights reserved.
Figure 18.23 IDC Interface AC Master Timing
Notes:
•
The C parameter is a programmable (from 2 - 1023) register field for
output clock frequency located in the IDC Clock (IDC_CLOCK)
register (see
Section 15.5.3, “SIO IDC Registers”
C = IDCSCL[9:0]
T
START
SIO_SCL (O)
SIO_SDA (I/O)
T
HD(O)
T
STOP
Data In
Data Out
T
HIGH
T
LOW
T
CYC
T
VALID(O)
T
SU(I)
T
HD(I)
Table 18.18 IDC Interface Master Timing Parameter
Param
Description
IDC Design Values (in sysclk cycles)
Min
Max
T
HIGH
High period of SIO_SCL(O)
8 + 2(C) + (S+1)(R)
7+2(C) + (S+1)(R+1)
T
LOW
Low period of SIO_SCL(O)
2(C)
T
CYC
Clock period of SIO_SCL(O)
8 + 4(C) + (S+1)(R)
7 + 4(C) + (S+1)(R+1)
T
START
Delay from SIO_SDA(O) falling to
next SIO_SCL(O) falling
(C)
T
STOP
Delay from SIO_SCL(O) rising to
SIO_SDA(O) rising
10 + 2(C) + (S+1)(R)
9 + 2(C) + (S+1)(R+1)
T
SU(I)
SIO_SDA(I) set up time before
SIO_SCL(O) rising
M{(S+1)(F-R) for SIO_SDA(I)
falling only, 0}
------
T
HD(I)
SIO_SDA(I) hold time after
SIO_SCL(O) rising
M{(S+1) for SIO_SDA(I) rising
after, (S+1)(R - F+1) for
SIO_SDA(I) falling after, 3}
------
T
VALID(
O)
Delay from SIO_SCL(O) falling to
SIO_SDA(O) valid
C + 2
T
HD(O)
SIO_SDA(O) hold time after
SIO_SCL(O) falling
C + 2