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I had spoken to Jason before the Launch(Thanks to @@adrianF for setting it up). He reassured that pricing will be fixed at $45.

@spirillis   You are amazing.  I have been so overwhelmed with getting things going for this huge education show we are doing in Atlanta, when I came in and saw your package on my desk.  I opened

@spirilis  request here are the photos from our Texas Based- Beagle Bone Black launch.  We went to CircuitCo (the people who are helping with the BYOBoosterpack contest) where BeagleBoard's birthpl

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Is it a limited quantity at $45 - or is that the price for a while?  Just wondering if I need to pick one up now rather than in a month or two.

 

Didn't read anything about any temporary price, $45 is it from what I know, they did a lot to drive the cost down.

I had spoken to Jason before the Launch(Thanks to @@adrianF for setting it up).

He reassured that pricing will be fixed at $45.

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So the BeagleBone's IRC channel is #beagle on Freenode.  A guy on there gave me a few articles he's written about the PRU, an interesting beast that seems shrouded in mystery (when you go searching for documentation).

 

From what I've gathered, the PRU (PRUSS v2 for these chips, officially called the PRU-ICSS in the Sitara AM3359 documentation, short for Programmable Real-Time Unit and Industrial Communication Subsystem) is a tiny purpose-built Microcontroller, of which there are 2 of them, living inside the Sitara CPU.

 

They have a very basic instruction set and are only programmed in ASM.  TI distributes PASM, the assembler for it.  Conceptually sounds like the Control Law Accelerator inside the C2000 DSP to me but this is specifically designed to support Industrial communication.  It has access to a few peripherals and has dedicated mux'd pins shared with the Sitara's GPIO pins.  It has 8KB program memory, 8KB RAM for data and a 12KB Shared Memory segment used to pass data to/fro the main CPU.  Runs at 200MHz.  Supports UART, Ethernet, some other stuff:

 

Supports protocols such as EtherCAT, PROFIBUS, PROFINET, EtherNet/IP

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From what I've gathered, the PRU (PRUSS v2 for these chips, officially called the PRU-ICSS in the Sitara AM3359 documentation, short for Programmable Real-Time Unit and Industrial Communication Subsystem) is a tiny purpose-built Microcontroller, of which there are 2 of them, living inside the Sitara CPU.

I've heard about these.  I was told that they are indeed Cortex M3 units, although that seems to confilct with your report.

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I've heard about these.  I was told that they are indeed Cortex M3 units, although that seems to confilct with your report.

Yeah my guess is someone saw "RISC" in the description and got happy... lol

 

This says it all: https://github.com/beagleboard/am335x_pru_package/blob/master/Documentation/01-AM335x_PRU_ICSS_Overview.pdf

 

 

Simple RISC ISA

- Approximately 40 instructions

- Logical, arithmetic, and flow control ops all

complete in a single cycle

 

 

Is not a general purpose RISC processor

- No multiply hardware/instructions

- No cache

- No pipeline

- No C programming

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@@bluehash I'm definitely feeling the whole idea of us having a BeagleBone subforum or forum or something.  Even if it's part of one of the existing forums, having a subforum to spam with threads should help us get each one of us up to speed quicker with the hardware and with Embedded Linux in general :smile:

Yes.. I'm prepping a forum.. I won't be able to put it in the Stellarisit forum as it is mainly M0/M3/M4. The beagle is an entirely different animal.

 

If we can group up, we can make a successful forum. i need a name though.. any ideas? This will support beagle bone and beagle board.

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I got 'em!

 

post-15991-0-22608500-1367091091_thumb.jpg

 

Your board is connected!


BeagleBone Black rev 0A5A S/N 1513BBBK0723 at 192.168.7.2

 

It was quite straightforward to get started, on my Mac it shows up as a USB mass storage drive and inside START.htm tells you what you need to do (installed a MacOS X driver for network-over-USB tethering type of stuff, typically used to tether to a cellphone for example)

Took a couple minutes but the Mac finally reported that network interface live, and http://192.168.7.2/ serves some Bonescript page right off the board.  Now to get a shell prompt...

 

post-15991-0-31162700-1367091068_thumb.jpg

post-15991-0-72448700-1367091075_thumb.jpg

post-15991-0-54218100-1367091083_thumb.jpg

 

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Looks like ssh root@192.168.7.2, password "root" gets you in...

 

 

root@beaglebone:/etc# cat /proc/cpuinfo 
processor : 0
model name : ARMv7 Processor rev 2 (v7l)
BogoMIPS : 297.40
Features : swp half thumb fastmult vfp edsp thumbee neon vfpv3 tls 
CPU implementer : 0x41
CPU architecture: 7
CPU variant : 0x3
CPU part : 0xc08
CPU revision : 2
 
Hardware : Generic AM33XX (Flattened Device Tree)
Revision : 0000
Serial : 0000000000000000

dmesg.txt

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Wow had a long wall-of-text post there with a bunch of stuff in different quote ... /quote sections, all but the first quote section got butchered!

 

Anyway, posting some general stuff:

 

Running processes: ps.txt

Loaded kernel modules: lsmod.txt

All available kernel modules: available_modules.txt

Kernel debug messages: dmesg.txt

 

Available CPU frequencies:

 

root@beaglebone:/sys/bus/cpu/devices/cpu0/cpufreq# for i in cpuinfo_*_freq; do
> echo -n $i': '; cat $i
> done
cpuinfo_cur_freq: 300000
cpuinfo_max_freq: 1000000
cpuinfo_min_freq: 300000
 
(CPU frequency scaling governor allows from 300MHz to 1.0GHz)
 
More detail on that:

root@beaglebone:/sys/bus/cpu/devices/cpu0/cpufreq# cat scaling_governor 
ondemand
root@beaglebone:/sys/bus/cpu/devices/cpu0/cpufreq# cat scaling_available_frequencies 
300000 600000 800000 1000000 
root@beaglebone:/sys/bus/cpu/devices/cpu0/cpufreq# cat scaling_available_governors 
conservative ondemand userspace powersave performance 
 

Supports 300MHz, 600MHz, 800MHz and 1.0GHz speeds.  Can peg it to 1.0GHz by changing the governor to "performance" I believe:

root@beaglebone:/sys/bus/cpu/devices/cpu0/cpufreq# echo performance > /sys/bus/cpu/devices/cpu0/cpufreq/scaling_governor 
root@beaglebone:/sys/bus/cpu/devices/cpu0/cpufreq# cat scaling_governor 
performance
root@beaglebone:/sys/bus/cpu/devices/cpu0/cpufreq# cat scaling_cur_freq 
1000000
root@beaglebone:/sys/bus/cpu/devices/cpu0/cpufreq# cat cpuinfo_cur_freq
1000000
 

 

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Humm... Wanted to try some of these for the DC barrel jack to supply more than 500mA for the VDD_5V rail on the expansion headers-

 

http://www.amazon.com/gp/product/B00AX45SRS/ref=oh_details_o01_s00_i01?ie=UTF8&psc=1

 

Plugged it into a 2.1A tablet charger then into the barrel jack, PWR LED turns on, then the user LEDs turn on one at a time but when the 4th one turns on, everything shuts off.

Plugged it into a 1A port on a portable rechargeable USB battery pack, the PWR LED turns on for a few seconds then shuts off.

I don't have a normal 5V wallwart to test against so I'll need to go get one to validate whether this cable just sucks or if there's a bug in the barrel jack hardware/interface.  Or if not, using a USB power port might just simply not work for that... (maybe the tablet expects to see some I/O to determine max power draw?)  I'm betting that is it, probably need an adapter with a chip to properly request full power from the port.

 

FWIW, plugging in the normal USB_A-to-miniB cable into that portable battery pack and powering it by the USB connector, it boots just fine.

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The USB network thing seems a bit flaky, half the time my Mac never gets its IP from the mini DHCP server on the 'bone.  Logged into the ttyO0 serial console with an FTDI and ran tcpdump, seems the USB network link is fine but the dhcp server isn't responding to the DHCPREQUEST packets clearly going over the wire.  Started a thread on the beagleboard forum's support section asking about it.

 

I think I should be able to manually set the Mac's IP on that interface to resolve it but haven't tried it yet.

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