Crash Ethernet with W5100

[agdl]

From @JanosAudron on April 11, 2013 20:37

Hardware: Arduino UNO + Ethernet Shield

Software: IDE 1.0.4 and 1.5.2

After some test I think the problem of the crash of W5100 chip that make it unresponsive is when you use an SD card, too. If you don't force pin 4 to HIGH, disabling the SD card, if these's a card insered the W5100 may become unresponsive. Maybe the bug is in SD library and not in Ethrnet library.

Copied from original issue: arduino/Arduino#1360

[agdl]

From @aShure on April 21, 2013 14:2

• Did you disable the W5100's SPI when you access the SD card? You should pull CS_W5100 high, e.g. Pin 10 on the official ethernet shield.
• You don't disable the SD card with pin 4 entirely, you just put it's SPI in a non-listening floating state so it won't interfere with the bus.
• There's a bug concerning the W5100's SPI when it's disabled - some pins are not put in a high impedance state.

[agdl]

From @JanosAudron on April 21, 2013 17:1

During my tests I had never used the SD card, but if it's present without force the pin 4 to high the communication on ethernet may crash.