EZ80F920120MOD Zilog, EZ80F920120MOD Datasheet - Page 157

• Manufacturer Part Number: EZ80F920120MOD
• Description: MODULE EZ80F92 512K 20MHZ
• Manufacturer: Zilog

Specifications of EZ80F920120MOD

• Module/board Type: Development Module
• Processor Series: EZ80F92x
• Core: eZ80
• Data Bus Width: 8 bit
• Program Memory Type: Flash
• Program Memory Size: 1 MB
• Interface Type: Cable
• Maximum Clock Frequency: 20 MHz
• Operating Supply Voltage: 0 V to 3.3 V
• Maximum Operating Temperature: + 70 C
• Mounting Style: SMD/SMT
• Package / Case: LQFP
• Development Tools By Supplier: eZ80F920200ZCOG
• Minimum Operating Temperature: 0 C
• For Use With/related Products: eZ80F92
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 269-3157; EZ80F920120MOD

PS015308-0404
Clock Synchronization
slave-transmitter must release the data line to allow the master to generate a STOP or a
repeated START condition.
Figure 34.I
All masters generate their own clocks on the SCL line to transfer messages on the I
Data is only valid during the High period of each clock.
Clock synchronization is performed using the wired AND connection of the I
to the SCL line, meaning that a High-to-Low transition on the SCL line causes the relevant
devices to start counting from their Low period. When a device clock goes Low, it holds
the SCL line in that state until the clock High state is reached. See Figure 35. The Low-to-
High transition of this clock, however, may not change the state of the SCL line if another
clock is still within its Low period. The SCL line is held Low by the device with the long-
est Low period. Devices with shorter Low periods enter a High wait-state during this time.
When all devices concerned count off their Low period, the clock line is released and goes
High. There is no difference between the device clocks and the state of the SCL line, and
all of the devices start counting their High periods. The first device to complete its High
period again pulls the SCL line Low. In this way, a synchronized SCL clock is generated
with its Low period determined by the device with the longest clock Low period, and its
High period determined by the one with the shortest clock High period.
by Transmitter
Data Output
Data Output
from Master
by Receiver
SCL Signal
2
C Acknowledge
START Condition
S
Clock Pulse for Acknowledge
P R E L I M I N A R Y
MSB
1
1
2
8
9
Product Specification
I2C Serial I/O Interface
eZ80F92/eZ80F93
2
C interfaces
2
C bus.
145