MSC8144E Reference Manual, Rev. 3
24-20
Freescale
Semiconductor
I
2
C
24.5.5 I
2
C Data Register (I2CDR)
Table 24-5 describes the I2CDR fields.
24.5.6 Digital Filter Sampling Rate Register (I2CDFSRR)
Table 24-6 describes the I2CDFSRR fields.
I2CDR
I
2
C Data Register
Offset 0x10
Bit
7
6
5
4
3
2
1
0
DATA
Type
R/W
Reset
0
0
0
0
0
0
0
0
Table 24-5. I2CDR Bit Descriptions
Name
Reset
Description
DATA
7–0
0
Data
Transmission starts when an address and the R/W bit are written to the data register and the I
2
C
interface performs as the initiator. A data transfer is initiated when data is written to the I2CDR.
The most significant bit is sent first in both cases. In the initiator receive mode, reading the data
register allows the read to occur, but also allows the I
2
C module to receive the next byte of data
on the I
2
C interface. In target mode, the same function is available after it is addressed.
I2CDFSRR
Digital Filter Sampling Rate Register
Offset 0x14
Bit
7
6
5
4
3
2
1
0
—
DFSR
Type
R/W
Reset
0
0
0
1
0
0
0
0
Table 24-6. I2CDFSRR Bit Descriptions
Name
Reset
Description
—
7–6
0
Reserved. Write to zero for future compatibility.
DFSR
5–0
010000
Digital Filter Sampling Rate
To assist in filtering out signal noise, the sample rate is programmed. This field is used to prescale
the frequency at which the digital filter takes samples from the I
2
C bus. The resulting sampling
rate is calculated by dividing the system frequency by the non-zero value of DFSR. If I2CDFSRR
is set to zero, the I
2
C bus sample points default to the reset divisor 0x10. The value of DFSR
should be defined by the system noise and the I2CFDR[FDR] value. DFSR must be less than six
times the division factor defined by I2CFDR[FDR].
Summary of Contents for MSC8144E
Page 1: ...MSC8144E Reference Manual Quad Core Media Signal Processor MSC8144ERM Rev 3 July 2009 ...
Page 48: ...MSC8144E Reference Manual Rev 3 xlviii Freescale Semiconductor ...
Page 86: ...MSC8144E Reference Manual Rev 3 1 38 Freescale Semiconductor Overview ...
Page 168: ...MSC8144E Reference Manual Rev 3 3 60 Freescale Semiconductor External Signals ...
Page 242: ...MSC8144E Reference Manual Rev 3 5 26 Freescale Semiconductor Reset ...
Page 314: ...MSC8144E Reference Manual Rev 3 8 24 Freescale Semiconductor General Configuration Registers ...
Page 414: ...MSC8144E Reference Manual Rev 3 10 14 Freescale Semiconductor MSC8144E SC3400 DSP Subsystem ...
Page 452: ...MSC8144E Reference Manual Rev 3 11 38 Freescale Semiconductor Internal Memory Subsystem ...
Page 520: ...MSC8144E Reference Manual Rev 3 12 68 Freescale Semiconductor DDR SDRAM Memory Controller ...
Page 1070: ...MSC8144E Reference Manual Rev 3 21 28 Freescale Semiconductor Timers ...