SMSC EVB8700, Руководство пользователя, Страница: 7 / 10

LAN8700 Evaluation Board User Manual
SMSC LAN8700
USER MANUAL
Revision 1.0 (02-23-10)
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Note 2.4 Resistor R12 acts as a pull-up on the MDIO pin. In most situations, the MAC circuitry
provides this pull-up and R12 is not required.
Note 2.5 Pins 11 and 21 of the J2 header both connect to resistor R52. This resistor must be
positioned correctly in order to divert the nINT/TX_ER/TXD4 pin of the LAN8700 to the
correct J2 location, as determined by the nINTSEL configuration strap value. Refer to
Section 2.2.3, "nINT/TX_ER/TXD4 Pin Configuration," on page 6 for additional information.
2.2.6 Switches
Table 2.6 J2 - 2x14 MII Header Pinout
HEADER
PIN DESCRIPTION
HEADER
PIN DESCRIPTION
1 Ground 15 TXD1
2 MDIO ( Note 2.4 ) 16 TXD2
3 MDC 17 TXD3
4 RXD3/nINTSEL 18 COL/MII/CRS_DV
5 RXD2/MODE2 19 CRS/PHYAD4
6 RXD1/MODE1 20 Ground
7 RXD0/MODE0 21 nINT ( Note 2.5 )
8 RX_DV 22 +3.3V
9 RX_CLK/REGOFF 23 +3.3V
10 RX_ER/RXD4 24 Ground
11 TX_ER/TXD4 ( Note 2.5 ) 25 +5V
12 TX_CLK 26 Ground
13 TX_EN 27 +5V
14 TXD0 28 Ground
Table 2.7 Switches
SWITCH DESCRIPTION FUNCTION
S1 Reset switch When pressed, triggers a board reset