Saturday, November 30, 2019

Jetson Nano and Raspberry Pi 4

December 2019
Jetson Nano and Raspberry Pi 4

Purchased a Jetson Nano when it first came out (5/22/2019) to try and understand its unique place in the Single Board Computer (SBC) space. This video from Explaining Computers can help understand the specifications and this video the artificial intelligence use case.

I found after a few months that the bare bones computer had been accessorized, so thought that should be written about. At the same time, Raspberry 4's came out, with a much lower price point than the Jetson Nano, but different use cases. So here is an attempt to show how them compare and contrast, possibly from a different perspective than most others.

To eliminate any suspense, here is a photo of my current accessorized Jetson Nano:

Which includes:
  • Audio board and headphones. (USB audio board w/PCM2704 chip, no microphone)
  • 120 GB USB 3.0 SSD 
  • MicroSD card
  • Transparent case with 5V fan
  • M.2 Key E WiFi/Bluetooth card & 2-antennas
  • Wireless trackball mouse
  • USB keyboard
  • Display-port graphics cable to a 
  • High quality curved 24" monitor.
  • Raspberry Pi Camera
Been using the Jetson Nano as a desktop for a few months now.

And here is a photo of a Raspberry Pi 4 with 4 GB of RAM.

Same monitor (HDMI), camera, keyboard and mouse is connected to this SBC. A Raspberry Pi 4 comes with audio, WiFi and Bluetooth, so those costs at about $30 aren't required with the new Raspberry Pi 4. Lets call it $62 to accessorize the Nano, not including the monitor, keyboard and mouse. Accessorizing the Raspberry Pi 4 (RPi4) also has small costs, especially if interested in speeding it up with a SSD. Inside the plastic housing the actual hardware is quite small. This can be folded into a case quite easily. Both the Nano and RPi4 can be configured to run off the USB 3 SSD.

Raspberry Pi 4 is small, lighter than the Nano developer kit, has audio (headphones output and microphone input). Both need a power-supply; the Jetson can use a standard USB micro 5 watt which you may have laying around. The Raspberry Pi 4 is now using the USB C, about the same price. Both need a Micro SD card.

I haven't tried the Jetson Nano with a high wattage power option yet, but comparing the two boards with an older performance benchmark called Octane they both have about the same score. I'm assuming with a larger power supply the Jetson Nano would have much higher benchmark score.

The differences between these two systems primarily comes down to graphical capabilities. The Jetson Nano has both an HDMI and a DisplayPort connection. The RPi4 two HDMI micros. But the real power of the Nano SBC comes from its ability to do image analysis. It will do artificial intelligence of recognition services very powerfully. The real heart of the Jetson Nano is the little card, called the NVIDIA Jetson Nano module. The bulk of what you buy when you get the developer kit is the carrier board. The carrier board is the piece with all the connections. The module is what does all the work. So you can program the module to go out in the world and do lots of work, mostly image analysis applications. I assume audio analysis will be next, but the NVIDIA world obviously didn't concentrate on this use case for the Nano because of the lack of on board audio interfaces.

One other observation of note. The Raspberry Pi community is head and shoulders better at supporting their offerings than NVIDIA. Yes, there are Jetson Nano user groups, but they are overly moderated, and not very informative when newbies ask questions. The Raspberry Pi community is quite forgiving.

I've seen lowered prices on the Nano at Newegg this holiday, and lowered in store priced RPi4 at Microcenter.

Wednesday, October 16, 2019

Around the Eye on the White Rim

by Jhose' Mc.
Oct. '19

This will be a quick report on the bike trip. Thursday afternoon my driver picked me up at the west light rail station and we were off. Heading west to Fruita where we met up with some of the team at the Hot Tomato pizza joint.

Good time re-acquainting, then Hotel La Quinta. Expensive bikes brought into rooms, other ones locked on bike rack on car. Morning breakfast was as expected, not worth writing about. Real coffee across the parking lot. Then we drove to the Eye in The Sky, waited. In the background some gas up and car shuttle activity was happening unbeknownst to me. To tell you the truth, I didn't know how cars, bikes and people were all going to be moving back and forth. When all the people arrived, we packed up three cars and waited for bikers to start the decent into, onto, down to the White Rim. 

First Day, Going Down

White Rim has a complete new meaning after having experienced it and can't be explained without having been there. But here is a try. The layers of Canyon Lands have different colors, depicting different eras of sedimentation. Rivers have carved away the rock layers revealing the history. The white layer on which we rode most of the White Rim must have been very hard to erode because it is the top layer a thousand or more feet above the rivers. Two rivers come together to form the midpoint of our particular journey, the Green on the right (as you go clockwise) and the Colorado river on the left. The first two days we were going along the meandering Colorado on its right. Up and down the White Rim path. Mostly white, sometimes red and if you didn't have glasses on you would see the blue. Still trying to figure out what oxidized element caused the blue. Everyone I asked had polarized glasses on and didn't see the azure. The third and forth days we had the Green River on our left, heading back to the Eye in the Sky visitor center. 

Similar to river trips, each day consisted of a routine.  Travel by bike or in a car, set camp, eat, break camp, pack, car or bike again, repeat till finished. There were drivers, cooks and clean up crews. And the best decaf coffee with ice cream and tequila and baileys. I just had the decaf as the certified always available designated driver. Camp sites varied some with shade, and others full sunlight and moon light. The moon greeted us each night soon after the sun set, typically rising over jagged rock then setting before most awoke. 

Here is a passage I wrote the first morning: 
Sitting here in limbo with Dan, six forty am, about an hour up. Constitutional, coffee, another coffee, and another constitutional. Teeth, everything is good.

Was dark at first with the light of the moon casting cathedral shadows across the plateau. Then that set, and the milky-way came out slightly, a glimpse of the infinity. The sun peaked over the east horizon with the terrain lines showing the southwest topography. You see this in southwest art, a black mountain range with rising colors. The light, or lack of light danced this morning. I could always see the outline of the campsite road, but couldn't see it in full sunlight yesterday afternoon.

We have eight tents, plus one where Mitch and Milan have two tadpoles quite close to each other, on a flat area at the bottom of the road. Camp A is higher up from the outhouse, a ridge-line protects from easterly winds. Not too many flat sites, but everyone manages.

The sky has a color pallet, black at the ground, orange at the ridge lines where the sun peaks out, yellow above that, light blue, darker blue then a dome of real blue till you get to the west where you can see the striped red rocks carved out by the river, hills and valleys, amphitheaters, spires, cathedrals. Man must have used these geometries as examples to build their worship structures to the gods, churches. The rocks glow red as the sun rises, but still not up. That cathedral is familiar. Seems to me I've camped at the river on the other side of it. I think we are at a point on the Colorado, above it. Five miles by road if you want to meander down, but maybe a thousand feet above. A point where the river hit resistance and carved a 360 turn. Someday it will all be flat, flattened by the trickle of water that carves forever. Slow forces which we are supposed to emulate in mediation. Water.

Our tent is right on the boundary line. Perhaps a tent or two are outside the boundary but I'm not sayin'. Practicing not being my father. I think it is my mother's birthday, if today is the 12th. Don't know the date, but do know her birthday. 89, she beat the curse of the Halligans / McCabes, all passing away at 87 until she came along; need to update my actuarial tables.

Driving the Jeep Cherokee was exhilarating, adding testosterone regardless of gender. You cannot see what you are driving over when going up the many steep hills. My head plastered to the top of the seating space trying to get the slightest glimpse of what is to come. Head hitting the side walls as left right wheels drop into holes or rise up to meet road ridges. "God I hope a jeep isn't coming the other way over that ridge." Could easily be a flat section that drops down, just as I am rising up. But no encounters on the road, trail, dusty sliver of a corridor. At one point the place where you are supposed to drive was right next to a 500 foot drop, shear rock. And no space to purchase on the other side of the car. I said to myself out loud "Shittt" and the Jeep's automatic voice recognition service came on loudly and startled me. I didn't hear exactly what was said because I was concentrating on not soiling myself. I imagined it saying, "Thanks for choosing Chrysler for your final car purchase."

Here is a video of two of the Jeeps making it up the steep climb the third day, both Jeeps go on three wheels. The other vehicle did the same thing, only much more ground clearance on that tire off the ground. That driver was having a GREAT time, the passenger wasn't. 

Reminds me of my uncle who was a NY taxi driver. Died peacefully in his sleep; not screaming for their lives like his passengers.  

Each day we became closer to our new friends, and understood our old friends better. Nothing too revealing. It was revealing when Cindy came down Murphy's Hogback long downhill run and passed me saying, "That was the greatest thing I have ever done". She has birthed a human, done extreme skiing, and other exhilarating things. I didn't know that speed and downhill was good for her. And where does being married 25 years fit into the whole equation? Oh well, no worries. 

The last day was longer, and more up-hilling than expected. And as it turns out I've been on the last part of Mineral Bottom Road, the rising for ever switch backs. Let me just say that the switch backs were in much better shape than the last times I've been on that road. This time there were no missing sections of road. But alas I did have an argument with my bike chain, which decided to go into hiding between the wheel hub and the largest sprocket. I will fix that soon, but wouldn't be able to on that road, so carried the back wheel up that hill. That wore me out, knowing full well the next day was going to be a hard recovery. And it was.

All in all, with a few mishaps, the gear worked. Cars, bikes, stoves, all got us back home fed, safe and sound. Thanks to all the team that supported me and Cindy. Great bike maintenance by Scott. I swear the chain lube was great. The real hero, the organized one, the guy who got the reservations early multiple days.... Buddha Dan. Thanks Rock Star Dan. 

Kevin was nice enough go get me and my tired legs back to the original starting point, where I drove back to a convenient place to catch Mike's car returning with Cindy. All worked out well and arrived back at home, trying to merge photos with others. Who took what photo will be left to the archivists. For now, we have the before photo with too many layers of clothing, and after photo with lots of red dusted skin showing. Amazing how that dusty sand got into everything including the psyche. Till next time, signing off. 

More memories, with captions

Dancing Wu Li Master Sitting Buddha

Self Portrait