NI Week Athena Announcement and Q&A Panel

[protoserge]

Originally Posted by Ether

FPGA?

The Zynq Chipset is a combined ARM Cortex A9 dual core and FPGA. Pretty cool if you ask me! I posted the links in one of my last posts, but here is the Zynq page: http://www.xilinx.com/products/silic...7000/index.htm

[pigpenguin]

Confused on servo power, due to lack of jumpers and everything. Is it software defined some how? Or will we need a separate board to run servos?

[Peter Johnson]

Originally Posted by pigpenguin

Confused on servo power, due to lack of jumpers and everything. Is it software defined some how? Or will we need a separate board to run servos?

It's definitely unclear. Specs 6V servo power so I guess it's software controlled.

[Peter Johnson]

Can anyone identify the connector being used for CAN bus? It almost looks like it only has two pins.. where are the +5V and ground pins?

[RufflesRidge]

Originally Posted by pigpenguin

Confused on servo power, due to lack of jumpers and everything. Is it software defined some how? Or will we need a separate board to run servos?

FRC speed controllers don't connect the power pin to anything, odds are that they just routed 6v to the power pin on all of the PWM pins.

Originally Posted by Peter Johnson

Can anyone identify the connector being used for CAN bus? It almost looks like it only has two pins.. where are the +5V and ground pins?

The CAN connector looks a lot like the power connector on the 2CAN. Probably just the two wires. As a differential bus CAN shouldn't need the 5V and GND being passed around.

[crake]

Originally Posted by RufflesRidge

FRC speed controllers don't connect the power pin to anything, odds are that they just routed 6v to the power pin on all of the PWM pins.

Correct. PWM power pins are 6V, and you get a couple of amps for driving servos.

The CAN connector looks a lot like the power connector on the 2CAN. Probably just the two wires. As a differential bus CAN shouldn't need the 5V and GND being passed around.

Correct as well - the CAN topology in this system does not distribute power. Power would be supplied to each device separately.

[Meshbeard]

Originally Posted by Peter Johnson

Can anyone identify the connector being used for CAN bus? It almost looks like it only has two pins.. where are the +5V and ground pins?

I'd assume that those two connectors are for the CAN-high and CAN-low wires. Power is probably separate since all the power systems on an FRC robot are separate from the controls.
What will likely happen is all of CTRE's new CAN stuff will have those two CAN ports separate from the regular old 12v power inputs on all the other components.

[donkehote]

i wish they had gotten a better toaster to record the webcast. I sincerely hope that the roborio can process better video quality than the webcast.

Joking aside, it looks great! I really like the smaller footprint, the lighter weight, and the canbus support. Do i see an optical port at the top next to the USB? would that be for faster camera response, or is it some other connector for something.

[Joe Ross]

Originally Posted by donkehote

Do i see an optical port at the top next to the USB? would that be for faster camera response, or is it some other connector for something.

Are you talking about the USB B connector? (To the left of the 2 USB A connectors)

[donkehote]

Originally Posted by Joe Ross

Are you talking about the USB B connector? (To the left of the 2 USB A connectors)

Oh, its a USB B, that's what it is. i was thinking it looked like the optical audio port and i was wondering what it would be for.

[Mark McLeod]

I believe Greg mentioned that the USB B port could be used to drop programs into the roboRIO.

[SoftwareBug2.0]

Originally Posted by Gregor

• C++ 11 will be used.

I'm pretty happy about that detail.

[Peter Johnson]

Originally Posted by RufflesRidge

The CAN connector looks a lot like the power connector on the 2CAN. Probably just the two wires. As a differential bus CAN shouldn't need the 5V and GND being passed around.

Originally Posted by crake

Correct as well - the CAN topology in this system does not distribute power. Power would be supplied to each device separately.

Originally Posted by Meshbeard

I'd assume that those two connectors are for the CAN-high and CAN-low wires. Power is probably separate since all the power systems on an FRC robot are separate from the controls.
What will likely happen is all of CTRE's new CAN stuff will have those two CAN ports separate from the regular old 12v power inputs on all the other components.

For robustness some systems pass around the control power. In these systems, the CAN bus control logic on each component is powered from the CAN bus power lines instead of the mains supply, ensuring the component is always reachable even if the mains supply to that component is lost (with optoisolation between the CAN control logic and the rest of the circuitry). This could be useful even in the FRC world: for example, tripping a breaker would not cause that CAN bus component (e.g. motor controller) to drop off the bus (so you could still pull status, and it could report it doesn't have mains power etc).

There is a serious problem with the current CAN layer where timeouts to Jaguars could swamp other parts of the system due to error spamming. As timeouts can be caused for multiple reasons (bad termination, disconnected cable, etc), regardless of the power distribution approach, my hope is that the software layer will be updated to avoid this issue.

[Mr V]

Originally Posted by Peter Johnson

For robustness some systems pass around the control power. In these systems, the CAN bus control logic on each component is powered from the CAN bus power lines instead of the mains supply, ensuring the component is always reachable even if the mains supply to that component is lost (with optoisolation between the CAN control logic and the rest of the circuitry). This could be useful even in the FRC world: for example, tripping a breaker would not cause that CAN bus component (e.g. motor controller) to drop off the bus (so you could still pull status, and it could report it doesn't have mains power etc).

Note the new PDB is CAN enabled so it can report a tripped breaker as well as the current flowing through each breaker. So you will be able to tell if something on the BUS isn't responding due to a tripped/cycling breaker.

[DonRotolo]

EDIT: There is a hardware connection within the Jags to prevent this (see posts following)

The current Jaguar CAN has us daisy-chaining network nodes, so if one drops the network, everything beyond it becomes unreachable.

In the automotive world, (most) CAN Buses have a star architecture, everyone hears everything, always.