ez80f92 ZiLOG Semiconductor, ez80f92 Datasheet - Page 167

• Manufacturer Part Number: ez80f92
• Description: Ez80acclaim Flash Microcontrollers
• Manufacturer: ZiLOG Semiconductor

PS015313-0508
I
The I2C_CCR register is a Write Only register. The seven LSBs control the frequency at
which the I
is in MASTER mode. The Write Only I2C_CCR registers share the same I/O addresses as
the Read Only I2C_SR registers. See
Table 90. I
The I
clock is f
In MASTER mode, the I
The use of two separately-programmable dividers allows the MASTER mode output fre-
quency to be set independently of the frequency at which the I
ture is particularly useful in multimaster systems because the frequency at which the I
bus is sampled must be at least 10 times the frequency of the fastest master on the bus to
ensure that START and STOP conditions are always detected. By using two programma-
ble clock divider stages, a high sampling frequency can be ensured while allowing the
MASTER mode output to be set to a lower frequency.
Bit
Reset
CPU Access
Note: W = Read only.
Bit
Position
7
[6:3]
M
[2:0]
N
f
f
2
SAMP
SCL
C Clock Control Register
2
=
C clocks are derived from the CPU system clock. The frequency of the CPU system
=
SCK
10 • (M + 1)(2)
2
2
C Clock Control Registers(I2C_CCR = 00CCh)
C bus is sampled and the frequency of the I
f
. The I
SCLK
2
N
f
SCLK
2
Value Description
0
0000–
1111
000–
111
C bus is sampled by the I
N
2
C clock output frequency on SCL (f
W
Reserved.
I
I
7
0
2
2
C clock divider scalar value.
C clock divider exponent.
W
6
0
Table
90.
W
5
0
2
C block at the frequency f
W
4
0
2
C clock line (SCL) when the I
W
3
0
SCL
2
C bus is sampled. This fea-
Product Specification
) is supplied by:
W
2
0
I2C Serial I/O Interface
SAMP
W
1
0
supplied by:
W
0
0
2
2
C
C
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