Digi NS9215 Computer Hardware User Manual


 
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TIMING
Memory Timing
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Ethernet timing All AC characteristics are measured with 10pF, unless otherwise noted.
The table below describes the values shown in the Ethernet timing diagrams.
Notes:
1 Minimum specification is for fastest AHB bus clock of 88.5 MHz. Maximum specification is
for slowest AHB bus clock of 51.6 MHz.
2
C
load = 10pf for all outputs and bidirects.
3 Minimum specification is for fastest AHB clock at 88.5 MHz.
Ethernet MII
timing
Parm Description Min Max Unit Notes
E1 MII tx_clk to txd, tx_en, tx_er 3 11 ns 2
E2 MII rxd, rx_en, rx_er setup to rx_clk rising 3 ns
E3 MII rxd, rx_en, rx_er hold from rx_clk rising 1 ns
E4 mdio (input) setup to mdc rising 10 ns
E5 mdio (input) hold from mdc rising 0 ns 2
E6 mdc to mdio (output) 18 34 ns 1, 2
E7 mdc period 80 ns 3
E6
E5
E4
E3
E2
E1
E7E7
tx_clk
txd[3:0],tx_en,tx_er
rx_clk
rxd[3:0],rx_en,rx_er
mdc
mdio (input)
mdio (output)