Nice write-up at LinuxGizmos -- why no PCIe?

That is a nice write up, thanks for the link.

Mike

Anyone got a magic decoder ring ?

For years, the Solo, which offers a 3G accelerator, but not an HD video accelerator, has been overshadowed by the dual- and quad-core i.MX6 models.

'For years'?  They were only released in late 2012 - my SL from that time has pre-release engineering sample SoC on it..

3G accelerator ?

Once again, the RIoTboard has the upper hand here, providing four USB 2.0 host ports, as well as a mini-USB OTG port. The Wandboard Solo has one each.

The SoC itself only has a single USB Host, The RIoT simply has an on-board 4 port hub.

Unlike the Wandboard, the RIoTboard adds JTAG

Actually, the wandboard has JTAG too, you just need to solder a connector: http://wiki.wandboard.org/index.php/Segger_J-Link

What linuxgizmos skips over is the RIoT's onboard OpenSDA, and I'm really not sure if It's a benefit or not myself after reading a bit about it.

Still, I'm not sure if I'd go for a Wandboard Solo or a RIoT board.  An established Wandboard community already exists, the RIoT is new enough that we don't yet know what will grow around it. Crucially, the wandboard already has support in mainline u-Boot and Linux kernel. There's generally some decent i.MX6 support out there and the RIoT will benefit from that, but even so it's still playing catch-up.

Hi John,

I managed to get hold of a RIoTboard and you're right. PCIe isn't hooked up.

It's listed as a feature in the datasheet of the processor, but mistakenly listed as a feature of the RIoTboard. Potentially you could solder in some wires (good luck) and break it out yourself from the processor (I wouldn't recommend it).

I'm told the documentation will be updated on Monday the 17th of February to reflect what is actually available on the board.

I don't know why it wasn't, I can only assume it was because of cost or it was considered that the Android OS wouldn't suitably support it (a big assumption on my part). Connectors are typically expensive which is why you don't get a great deal of them on developer boards.

Christopher Stanton wrote:

 

Hi John,

 

I managed to get hold of a RIoTboard and you're right. PCIe isn't hooked up.

 

It's listed as a feature in the datasheet of the processor, but mistakenly listed as a feature of the RIoTboard. Potentially you could solder in some wires (good luck) and break it out yourself from the processor (I wouldn't recommend it).

 

I'm told the documentation will be updated on Monday the 17th of February to reflect what is actually available on the board.

 

I don't know why it wasn't, I can only assume it was because of cost or it was considered that the Android OS wouldn't suitably support it (a big assumption on my part). Connectors are typically expensive which is why you don't get a great deal of them on developer boards.

The RIoTboard User Manual v1.0 lists PCIe as part of the processor summary, but from what I can tell the UM never suggests that PCIe is available to users.  The RioTboard schematics V1.0 schematics clearly show that PCIe is not hooked up (sheet 8).

Having an optional PCIe connector is dirt cheap -- just don't populate it.  The problem is to decide which connector to use.  Personally, I think a SATA connector would be dandy, since then you can get a cheap, reliable cable to connect PCIe to something else.

My personal interest in PCIe is that I have an FPGA design I did for a client.  I update the design every year or so to add capabilities.  Right now it has a PCI interface, which works fine.  However, I fear that a future design will require PCIe to talk to a future processor.  I don't need PCIe for the speed -- just for the connectivity.  So I keep a close watch on development boards with PCIe.  With luck, a cheap development board with PCIe will arrive at the same time as a cheap FPGA with PCIe.