DRAFT
DRAFT DRAFT DR
DRAFT DRAFT DRAFT
D
RAF
DRAFT DRAFT DRA
FT D
RAFT DR
AFT D
DRA
FT DRAFT DRAFT
D
RAFT
DRAFT
D
RAFT
DRA
UM10601
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2012. All rights reserved.
Preliminary user manual
Rev. 1.0 — 7 November 2012
198 of 313
NXP Semiconductors
UM10601
Chapter 16: LPC800 I2C-bus interface
16.6.9 Master Time
The MSTTIME register allows programming of certain times that may be controlled by the
Master function. These include the clock (SCL) high and low times, repeated Start setup
time, and transmitted data setup time.
The I2C clock pre-divider is described in
2
MSTSTOP
Master Stop control. This bit is write-only.
0
0
No effect.
1
Stop. A Stop will be generated on the I
2
C bus at the next
allowed time, preceded by a Nack to the slave if the
master is receiving data from the slave (Master Receiver
mode).
31:
2
-
Reserved. Read value is undefined, only zero should be
written.
NA
Table 179. Master Control register (MSTCTL, address 0x4005 0020) bit description
Bit Symbol
Value Description
Reset
value
Table 180. Master Time register (MSTTIME, address 0x4005 0024) bit description
Bit
Symbol
Value Description
Reset
value
2:0
MSTSCLLOW
Master SCL Low time. Specifies the minimum low time
that will be asserted by this master on SCL. Other devices
on the bus (masters or slaves) could lengthen this time.
This corresponds to the parameter t
LOW
in the I
2
C bus
specification. I
2
C bus specification parameters t
BUF
and
t
SU;STA
have the same values and are also controlled by
MSTSCLLOW.
0
0x0
2 clocks. Minimum SCL low time is 2 clocks of the I
2
C
clock pre-divider.
0x1
3 clocks. Minimum SCL low time is 3 clocks of the I
2
C
clock pre-divider.
0x2
4 clocks. Minimum SCL low time is 4 clocks of the I
2
C
clock pre-divider.
0x3
5 clocks. Minimum SCL low time is 5 clocks of the I
2
C
clock pre-divider.
0x4
6 clocks. Minimum SCL low time is 6 clocks of the I
2
C
clock pre-divider.
0x5
7 clocks. Minimum SCL low time is 7 clocks of the I
2
C
clock pre-divider.
0x6
8 clocks. Minimum SCL low time is 8 clocks of the I
2
C
clock pre-divider.
0x7
9 clocks. Minimum SCL low time is 9 clocks of the I
2
C
clock pre-divider.