zl50415 Zarlink Semiconductor, zl50415 Datasheet - Page 18

• Manufacturer Part Number: zl50415
• Description: Managed 16-port 10/100 M + 2-port 1 G Ethernet Switch
• Manufacturer: Zarlink Semiconductor

If a master receiver does not acknowledge after any byte, then the slave transmitter must release the SDA line to let
the master generate the Stop condition.
2.4.5
After the first byte containing the address, all bytes that follow are data bytes. Each byte must be followed by an
acknowledge bit. Data is transferred MSB first.
2.4.6
Generated by the master. The bus is considered to be free after the Stop condition is generated. The Stop condition
occurs if while the SCL line is High, there is a Low-to-High transition of the SDA line.
The I
slave is the EEPROM memory.
2.5
The synchronous serial interface serves the function of configuring the ZL50418 not at boot time but via a PC. The
PC serves as master and the ZL50418 serves as slave. The protocol for the synchronous serial interface is nearly
identical to the I
transferred.
The unmanaged ZL50418 uses a synchronous serial interface to program the internal registers. To reduce the
number of signals required the register address, command and data are shifted in serially through the D0 pin.
STROBE- pin is used as the shift clock. AUTOFD- pin is used as data return path.
Each command consists of four parts.
•
•
•
•
Any command can be aborted in the middle by sending an ABORT pulse to the ZL50418.
A START command is detected when D0 is sampled high when STROBE- rise and D0 is sampled low when
STROBE- fall.
An ABORT command is detected when D0 is sampled low when STROBE- rise and D0 is sampled high when
STROBE- fall.
START pulse
Register Address
Read or Write command
Data to be written or read back
2
C interface serves the function of configuring the ZL50418 at boot time. The master is the ZL50418, and the
Synchronous Serial Interface
Data
Stop Condition
2
C protocol. The main difference is that there is no acknowledgment bit after each byte of data
Zarlink Semiconductor Inc.
ZL50418
18
Data Sheet