Texas Instruments THUNDER TNETX3270 User Manual
Page 60
TNETX3270
ThunderSWITCH
24/3 ETHERNET
SWITCH
WITH 24 10-MBIT/S PORTS AND 3 10-/100-MBIT/S PORTS
SPWS043B – NOVEMBER 1997 – REVISED APRIL 1999
60
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
serial MII management interface
timing requirements (see Figure 20)
NO.
MIN
MAX
UNIT
1
tsu(MDIO)
Setup time, MDIO valid before OSCIN
↑
, read
7
ns
2
th(MDIO)
Hold time, MDIO valid after OSCIN
↑
, read
3
ns
operating characteristics over recommended operating conditions (see Figure 20)
NO.
PARAMETER
MIN
MAX
UNIT
3
td(MDIO)
Delay time, from OSCIN
↑
to MDIO valid, write
11
ns
4
td(MDCLK)
Delay time, from OSCIN
↑
to MDCLK
↑
11
ns
5
td(MRESET)
Delay time, from OSCIN
↑
to MRESET
↓
11
ns
6
tdis(MDIO)
Disable time, from OSCIN
↑
to after MDIO to Z state, read
11
ns
7
tdis(MDCLK)
Disable time, from OSCIN
↑
to after MDCLK to Z state
11
ns
8
tdis(MRESET) Disable time, from OSCIN
↑
to after MRESET to Z state
11
ns
9
ten(MDIO)
Enable time, from OSCIN
↑
to before MDIO valid
11
ns
10
ten(MDCLK)
Enable time, from OSCIN
↑
to before MDCLK valid
11
ns
11
ten(MRESET)
Enable time, from OSCIN
↑
to before MRESET valid
11
ns
OSCIN
(input)
MDCLK
(output)
MRESET
(output)
MDIO
(input/
output)
1
6
9
2
3
7
10
8
4
5
Z
Z
Z
Read Input
Write Output
11
Figure 20. Serial MII Management Read/Write Cycle