Can I connect SwitchBlox Rugged (100BASE-Tx) to SPEBlox (1000BASE-T1)?

We’ve encountered an issue with our prototype system that utilizes the SwitchBlox Rugged ethernet switch and SPEBlox media converter (RevF).

We need to connect the SwitchBlox Rugged to the SPE blox.

Do you have a 8pos-to-4pos PicoBlade wire harness in the catalog for this purpose that you could sell us?

If not, do you have any guidance / recommendations on how best to build or obtain a harness to make this connection?

Unfortunately, this is not going to be possible as is.

SPEBlox (I’m talking about SPEBlox, the 1Gbps device, not SPEBlox Long, which is a 10Mbps device) can only work at 1000Mbps, both on the SPE side and the standard ethernet side. That means to form a connection with SPEBlox, you need to connect a standard 1000BASE-T on the standard ethernet side. From that connection, SPEBlox, will convert that to a 1000BASE-T1 single pair ethernet connection. There is no ability for the device to autonegotiate to work at 100Mbps on either side. In other words, SPEBlox is not 100BASE-Tx or 100BASE-T1 compatible.

SwitchBlox Rugged is 100BASE-Tx device and thus, if you connect it to SPEBlox, (even using a 4 way to 8 way cable), you’re not going to see a link. This is different to our other hardware where you can easily connect a gigabit switch to a 100M switch simply by using a 4 way cable.

The reason for this is that SPEBlox is not capable of achieving autonegotiation. Unfortunately this is a limitation in the chips currently available for SPE.

A work-around for this is to connect something like GigaBlox Nano between SwitchBlox Rugged and SPEBlox. GigaBlox Nano can accept a 100M connection from the SwitchBlox Rugged, and then frame this into 1Gbps data which SPEBlox will accept. This isn’t super elegant, but it will work. If you need to maintain your temperature rating, you’d have to use a something more pricey like GigaBlox Rugged, which is unfortunate.