MC44BC373 MOTOROLA [Motorola, Inc], MC44BC373 Datasheet - Page 19

• Manufacturer Part Number: MC44BC373
• Description: Multi-Standard or PAL/ NTSC Modulator with integrated antenna booster/splitter ICs
• Manufacturer: MOTOROLA [Motorola, Inc]

13.3 Levels Definition
13.4 High-Speed I
13.5 I
The bus receiver operates the I
In write mode, each ninth data bit (bits 9, 18, 27, 36, and 45) is an acknowledge bit (ACK) during which
the MCU sends a logic 1 and the Modulator circuit answers on the data line by pulling it low. Besides the
chip address, the circuit needs two or four data bytes for operation. The following data byte sequences are
the permitted incoming information:
After the chip address, two or four data bytes may be received.
MOTOROLA
SDA
SCL
STA
•
•
If three (3) data bytes are received, the third one is ignored.
If five (5) or more data bytes are received, the fifth and following ones are ignored, and the last ACK
pulse is sent at the end of the fourth data byte.
1 1 0 0 1 0 1 0 (ACK) = $CA (hex) in write mode
Example 1
Example 2
Example 3
Example 4
With:
STA = Start condition
FM = Frequency information, high order bits
C1 = Control information, high order bits
STO = Stop condition
2
C Write Mode Format and Bus Receiver
1
Chip Address ($CA)
2
3
4
STA
STA
STA
STA
Freescale Semiconductor, Inc.
SDA
5
2
For More Information On This Product,
2
C Compatible Bus Format
C compatible data format. The chip address (I
6
Figure 13. SCL and SDA Bus Timing
...
7
MC44BC373/374 Technical Data
CA
CA
CA
CA
Go to: www.freescale.com
8
Vcc
Vih
Vil
0V
Figure 12. SDA Levels
ACK
9 10
First Data Byte (C1 or FM)
FM
FM
C1
C1
11 12 13
CA = Chip Address
FL = Frequency information, low order bits
CO = Control information, low order bits
C0
FL
C0
FL
14
dead band
15
STO
STO
FM
C1
16 17 18
High-Speed I
ACK
C0
FL
2
C bus) is:
19
Data
2
STO
STO
C Compatible Bus
44
ACK
45
Stop
19