pcd3312c NXP Semiconductors, pcd3312c Datasheet - Page 12

• Manufacturer Part Number: pcd3312c
• Description: Dtmf/modem/musical-tone Generators
• Manufacturer: NXP Semiconductors

Philips Semiconductors
8.3
A device generating a message is a ‘transmitter’, a device receiving a message is the ‘receiver’. The device that controls
message transfer is the ‘master’ and the devices that are controlled by the master are the ‘slaves’.
8.4
The number of data bytes transferred between the start and stop conditions from transmitter to receiver is not limited.
Each byte of eight bits is followed by one acknowledge bit. The acknowledge bit is a HIGH level put on the bus by the
transmitter whereas the master generates an extra acknowledge after the reception of each byte. Also a master must
generate an acknowledge after reception of each byte that has been clocked out of the slave transmitter. The device that
acknowledges has to pull down the SDA line during the acknowledge-related clock pulse. Set-up and hold times must
be taken into account to ensure that the SDA line is stable LOW during the whole HIGH period of the
acknowledge-related clock pulse. A master receiver must signal an end of data to the transmitter by not generating an
acknowledge on the last byte that has been clocked out of the slave. In this event the transmitter must leave the data
line HIGH to enable the master to generate the stop condition.
1996 Nov 21
DTMF/modem/musical-tone generators
System configuration (see Fig.9)
Acknowledge
SDA
SCL
TRANSMITTER /
BY TRANSMITTER
RECEIVER
MASTER
DATA OUTPUT
DATA OUTPUT
BY RECEIVER
SCL FROM
MASTER
CONDITION
START
RECEIVER
Fig.10 Acknowledgment on the I
SLAVE
S
Fig.9 System configuration.
1
TRANSMITTER /
RECEIVER
12
SLAVE
2
2
C-bus.
TRANSMITTER
MBC602
MASTER
not acknowledge
PCD3311C; PCD3312C
acknowledge
8
acknowledgement
clock pulse for
TRANSMITTER /
9
RECEIVER
MASTER
Product specification
MBA605