KSZ8893-MQL Micrel Semiconductor, Inc., KSZ8893-MQL Datasheet - Page 45

• Manufacturer Part Number: KSZ8893-MQL
• Description: Integrated 3-Port 10/100 Managed Switch with PHYs
• Manufacturer: Micrel Semiconductor, Inc.

The following is a sample procedure for programming the KSZ8893MQL using the SPI bus:
1. At the board level, connect the KSZ8893MQL pins as follows:
2. Enable SPI slave mode by setting the KSZ8893MQL strap-in pins PS[1:0] (pins 100 and 101, respectively) to
3. Power up the board and assert reset to the KSZ8893MQL.
4. Configure the desired register settings in the KSZ8893MQL, using the SPI write or multiple write command.
5. Read back and verify the register settings in the KSZ8893MQL, using the SPI read or multiple read
6. Write a ‘1’ to the “Start Switch” bit to start the KSZ8893MQL with the programmed settings.
Note: The “Start Switch” bit cannot be set to ‘0’ to stop the switch after an ‘1’ is written to this bit. Thus, it is
recommended that all switch configuration settings are programmed before the “Start Switch” bit is set to ‘1’.
Some of the configuration settings, such as “Aging enable”, “Auto Negotiation Enable”, “Force Speed” and “Power
down” can be programmed after the switch has been started.
The following four figures illustrate the SPI data cycles for “Write”, “Read”, “Multiple Write” and “Multiple Read”.
The read data is registered out of SPIQ on the falling edge of SPIC, and the data input on SPID is registered on
the rising edge of SPIC.
Micrel
November 2005
“10”.
After reset, the “Start Switch” bit (register 1 bit [0]) is set to ‘0’.
command.
SPIS_N
SPIQ
SPIC
SPID
KSZ8893MQL Pin #
99
97
98
96
X
0
0
WRITE COMMAND
0
KSZ8893MQL Signal Name
SPIS_N
SCL
(SPIC)
SDA
(SPID)
SPIQ
0
Table 15. KSZ8893MQL SPI Connections
0
Figure 8. SPI Write Data Cycle
0
1
0
A7 A6 A5 A4 A3 A2 A1 A0
45
WRITE ADDRESS
SPI Slave Select
SPI Clock
SPI Data
(Master output; Slave input)
SPI Data
(Master input; Slave output)
External Processor Signal Description
D7
D6
D5
WRITE DATA
D4
D3
KSZ8893MQL/MQLI
D2
M9999-111705
D1
D0