Don't know if you are generally aware of this, but it looks like there could be further delays to the Pi according to a recent blog post:
Incorrect RJ-45 sockets sourced by the manufacturers....
Don't know if you are generally aware of this, but it looks like there could be further delays to the Pi according to a recent blog post:
Incorrect RJ-45 sockets sourced by the manufacturers....
I guess I don't understand how we are at this point. My understanding was that the manufacturer was done with the first 10k on 20 Feb. At that point the team from the Foundation were on site to test the boards. If you read the RPi blog link in the first post, the author said that without the right RJ-45 port, there is no ethernet. What kind of test was done that didn't find that the ethernet was not working? I've seen the Newark date on their website move to 27 July, likely due to the rework on the original batch and the delays sourcing proper parts and making the next batches.
I assume that at one point the team of the Foundation, RS and Farnell will determine how many they need to fill current demand (paid orders) and to stock shelves for future orders. At that point they can make an order from China and get delivery dates. I'm happy with the effort that all parties are putting in, but at the same time I am severely disappointed that I likely won't get the RPi I ordered until 6 months later. I still say that the launch should have been delayed until all of the original 10k units were on the tested and on the shelves at RS and Farnell. This situation doesn't bode well when no one is sure that parts exist to make more RPi's.
I guess I don't understand how we are at this point. My understanding was that the manufacturer was done with the first 10k on 20 Feb. At that point the team from the Foundation were on site to test the boards. If you read the RPi blog link in the first post, the author said that without the right RJ-45 port, there is no ethernet. What kind of test was done that didn't find that the ethernet was not working? I've seen the Newark date on their website move to 27 July, likely due to the rework on the original batch and the delays sourcing proper parts and making the next batches.
I assume that at one point the team of the Foundation, RS and Farnell will determine how many they need to fill current demand (paid orders) and to stock shelves for future orders. At that point they can make an order from China and get delivery dates. I'm happy with the effort that all parties are putting in, but at the same time I am severely disappointed that I likely won't get the RPi I ordered until 6 months later. I still say that the launch should have been delayed until all of the original 10k units were on the tested and on the shelves at RS and Farnell. This situation doesn't bode well when no one is sure that parts exist to make more RPi's.
Actually the substituted jacks would work, though only reliably on short cable runs. More importantly they would be considered illegal in many jurisdictions as there would now be no electrical isolation between the Pi side and the LAN side as well as no impedance matching which is required for long cable runs for signal integrity.
Non magnetic (no transformers) jacks are fine to use, but then the equipment normally has the transformer as a separate component - look inside an old modem and you'll see the transformer. Because the Pi was designed to be small that requires the network jack to have the transformer built into the jack.
How they found out they haven't siad, but it could have been they tested signal reflection on a long network cable or they were getting unreliable signal integrity or they simply measured the resistance between pin pairs and found it too low. Some nice X-ray pictures are on the R-pi site.
The pinout of an Ethernet jack with magnetics may be different from a non-magnetic jack. If you look at the RasPi PC boards (there are links at http://elinux.org/Rpi_Hardware) it looks like the Enet differential pairs go to connector pins 1+3 and 4+6, which is one of the possible pinouts for the PCB side of a magnetic jack. For a non-magnetic jack the pairs would be 1+2 and 3+6, the same as an Ethernet cable. Given this, it would be obvious that Ethernet wasn't working. The RasPi designers are lucky that they didn't use a magnetic jack with pairs on 1+2 and 3+6, as they may not have noticed that the magnetics were missing.