NXP Semiconductors KL25 Series - I2 C Programmable Input Glitch Filter Register (I2 Cx_Flt)

I2Cx_C2 field descriptions (continued)
Field Description
0 Normal drive mode
1 High drive mode
4
SBRC
Slave Baud Rate Control
Enables independent slave mode baud rate at maximum frequency, which forces clock stretching on SCL
in very fast I2C modes. To a slave, an example of a "very fast" mode is when the master transfers at 40
kbps but the slave can capture the master's data at only 10 kbps.
0 The slave baud rate follows the master baud rate and clock stretching may occur
1 Slave baud rate is independent of the master baud rate
3
RMEN
Range Address Matching Enable
This bit controls slave address matching for addresses between the values of the A1 and RA registers.
When this bit is set, a slave address match occurs for any address greater than the value of the A1
register and less than or equal to the value of the RA register.
0 Range mode disabled. No address match occurs for an address within the range of values of the A1
and RA registers.
1 Range mode enabled. Address matching occurs when a slave receives an address within the range of
values of the A1 and RA registers.
2–0
AD[10:8]
Slave Address
Contains the upper three bits of the slave address in the 10-bit address scheme. This field is valid only
while the ADEXT bit is set.
38.3.7 I2C Programmable Input Glitch Filter register (I2Cx_FLT)
Address: Base address + 6h offset
Bit 7 6 5 4 3 2 1 0
Read
SHEN
STOPF
STOPIE FLT
Write w1c
Reset
0 0 0 0 0 0 0 0
I2Cx_FLT field descriptions
Field Description
7
SHEN
Stop Hold Enable
Set this bit to hold off entry to stop mode when any data transmission or reception is occurring.
The following scenario explains the holdoff functionality:
1. The I2C module is configured for a basic transfer, and the SHEN bit is set to 1.
2. A transfer begins.
3. The MCU signals the I2C module to enter stop mode.
4. The byte currently being transferred, including both address and data, completes its transfer.
5. The I2C slave or master acknowledges that the in-transfer byte completed its transfer and
acknowledges the request to enter stop mode.
6. After receiving the I2C module's acknowledgment of the request to enter stop mode, the MCU
determines whether to shut off the I2C module's clock.
Table continues on the next page...
Chapter 38 Inter-Integrated Circuit (I2C)
KL25 Sub-Family Reference Manual, Rev. 3, September 2012
Freescale Semiconductor, Inc. 697