NXP Semiconductors LPC11U3x User Manual

UM10462 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2016. All rights reserved.
User manual Rev. 5.5 — 21 December 2016 308 of 523
NXP Semiconductors
UM10462
Chapter 14: LPC11U3x/2x/1x I2C-bus controller
• Master Receiver
• Slave Receiver
• Slave Transmitter
Data transfers in each mode of operation are shown in Figure 49
, Figure 50, Figure 51,
Figure 52
, and Figure 53. Table 285 lists abbreviations used in these figures when
describing the I
2
C operating modes.
In Figure 49 to Figure 53, circles are used to indicate when the serial interrupt flag is set.
The numbers in the circles show the status code held in the STAT register. At these points,
a service routine must be executed to continue or complete the serial transfer. These
service routines are not critical since the serial transfer is suspended until the serial
interrupt flag is cleared by software.
When a serial interrupt routine is entered, the status code in STAT is used to branch to the
appropriate service routine. For each status code, the required software action and details
of the following serial transfer are given in tables from Table 287
to Table 293.
14.10.1 Master Transmitter mode
In the master transmitter mode, a number of data bytes are transmitted to a slave receiver
(see Figure 49
). Before the master transmitter mode can be entered, I2CON must be
initialized as follows:
The I
2
C rate must also be configured in the SCLL and SCLH registers. I2EN must be set
to logic 1 to enable the I
2
C block. If the AA bit is reset, the I
2
C block will not acknowledge
its own slave address or the General Call address in the event of another device
becoming master of the bus. In other words, if AA is reset, the I
2
C interface cannot enter
slave mode. STA, STO, and SI must be reset.
Table 285. Abbreviations used to describe an I
2
C operation
Abbreviation Explanation
S START Condition
SLA 7-bit slave address
R Read bit (HIGH level at SDA)
W Write bit (LOW level at SDA)
A Acknowledge bit (LOW level at SDA)
A
Not acknowledge bit (HIGH level at SDA)
Data 8-bit data byte
P STOP condition
Table 286. CONSET used to initialize Master Transmitter mode
Bit 7 6 5 4 3 2 1 0
Symbol - I2EN STA STO SI AA - -
Value- 1000x- -

NXP Semiconductors LPC11U3x Specifications

General

Brand	NXP Semiconductors
Model	LPC11U3x
Category	Microcontrollers
Language	English