Datasheet
2016 Microchip Technology Inc. DS00002246A-page 53
KSZ8895MQX/RQX/FQX/MLX
Note 4-1 148,800 frames/sec × 50 ms/interval × 1% = 74 frames/interval (approx.) = 0x4A.
5 - 4
CPU
interface
clock select
Select the internal clock speed for SPI, MDI inter-
face:
00 = 41.67 MHz (SPI up to 6.25 MHz, MDC up to
6MHz)
01 = 83.33 MHz Default (SPI SCL up to 12.5 MHz,
MDC up to 12 MHz)
10 = 125 MHz (for high speed SPI about 25 MHz)
11 = Reserved
R/W 01
3 Reserved N/A Do not change RO 0
2
Enable
restore
preamble
This bit is to enable PHY5, when in 10BT mode, to
restore preamble before sending data on P5-MII
interface.
1 = Enable PHY5 to restore preamble.
0 = Disable PHY5 to restore preamble.
R/W 1
1
Tail Tag
Enable
Tail Tag feature is applied for Port 5 only.
1 = Insert 1 Byte of data right before FCS
0 = Do not insert
R/W 0
0
Pass Flow
Control
Packet
1 = Switch will not filter 802.1x “flow control”
packets
0 = Switch will filter 802.1x “flow control” packets
R/W 0
Register 13 (0x0D): Global Control 11
7 - 0
Factory
Testing
N/A Do not change RO 00000000
Register 14 (0x0E): Power Down Management Control 1
7 Reserved N/A Do not change RO 0
6 Reserved N/A Do not change RO 0
5
PLL Power
Down
PLL power down enable:
1 = Disable
0 = Enable
R/W 0
4 - 3
Power
Manage-
ment Mode
Power management mode:
00 = Normal mode (D0)
01 = Energy Detection mode (D2)
10 = Soft Power Down mode (D3)
11 = Power Saving mode (D1)
Note: For Soft Power Down mode to take effect,
have to write ‘10’ only without read value back.
R/W
00
Pin LED[4][0] strap
option.
PD(0): Select Energy
detection mode
PU(1): (default) Nor-
mal mode
Note: LED[4][0] has
internal pull-up.
2 - 0 Reserved N/A Do not change RO 000
Register 15 (0x0F): Power Down Management Control 2
7 - 0
Go_sleep_-
time[7:0]
When the Energy Detect mode is on, this value is
used to control the minimum period that the no
energy event has to be detected consecutively
before the device enters the low power state. The
unit is 20 ms. The default of go sleep time is 1.6
seconds (80 Dec x 20 ms).
R/W 01010000
TABLE 4-2: GLOBAL REGISTER DESCRIPTIONS (CONTINUED)
Address Name Description Mode Default