KS8893ML MICREL [Micrel Semiconductor], KS8893ML Datasheet - Page 45

• Manufacturer Part Number: KS8893ML
• Description: Integrated 3-Port 10/100 Managed Switch with PHYs Preliminary Data Sheet Rev. 1.0
• Manufacturer: MICREL [Micrel Semiconductor]

The following is a sample procedure for programming the KS8893M using the SPI bus:
1. At the board level, connect the KS8893M pins as follows:
2. Enable SPI slave mode by setting the KS8893M strap-in pins PS[1:0] (pins 100 and 101, respectively) to “10”.
3. Power up the board and assert reset to the KS8893M.
4. Configure the desired register settings in the KS8893M, using the SPI write or multiple write command.
5. Read back and verify the register settings in the KS8893M, using the SPI read or multiple read command.
6. Write a ‘1’ to the “Start Switch” bit to start the KS8893M 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.
June 2005
After reset, the “Start Switch” bit (register 1 bit [0]) is set to ‘0’.
SPIS_N
SPIQ
SPIC
SPID
KS8893M Pin #
99
97
98
96
X
0
0
WRITE COMMAND
0
KS8893M Signal Name
SPIS_N
SCL
(SPIC)
SDA
(SPID)
SPIQ
0
Table 15. KS8893M SPI Connections
0
Figure 8. SPI Write Data Cycle
0
1
0
A7 A6 A5 A4 A3 A2 A1 A0
45
WRITE ADDRESS
External Processor Signal Description
SPI Slave Select
SPI Clock
SPI Data
(Master output; Slave input)
SPI Data
(Master input; Slave output)
D7
D6
D5
WRITE DATA
D4
D3
D2
M9999-063005
D1
D0