Difference between revisions of "BeagleBone/GeigerCapePrototype"

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(Design)
(Tubes Tested)
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== Introduction ==
 +
 +
{|  border="1" cellspacing="0" cellpadding="4"
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|- bgcolor="#c0e0e0"
 +
| '''Name'''
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| '''Role'''
 +
|-
 +
| Matt Ranostay
 +
| Backup HW design/Userspace applications/Presenter
 +
|-
 +
| Dimitris Sapountzakis
 +
| HW design
 +
|-
 +
| Pantelis Antoniou
 +
| Cape Manager + DT overlay support
 +
|-
 +
|}
 +
 +
Winner of Beagleboard.org Cape Contest <ref name="cape_winner" />
 +
 
== Design ==
 
== Design ==
  
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* Fix current limiter with op-amps
 
* Fix current limiter with op-amps
 
* Use resistors that are within spec
 
* Use resistors that are within spec
* eCAP support to get rid of pulse extender part of PCB
+
* eCAP support to reduce the need of the pulse extender part of PCB, using a small ceramic capacitor versus 1 uF electrolytic one, and which in turn will reduce "dead time".
  
 
== Software ==
 
== Software ==
Line 18: Line 38:
 
There are demo applications available in the links below.
 
There are demo applications available in the links below.
  
Communication with the cape is using Capebus driver interface (example output below):
+
Communication with the cape is using Pantelis Antoniou's Capemanager + DT overlays driver interface (example output below):
  
 
<pre>
 
<pre>
Confirm Capebus picked up device
+
Confirm Cape Manager picked up device
# cd /sys/bus/capebus/devices/bone-0\:3
+
# cd /sys/devices/ocp.2/bone-cape-geiger.11
# cat id
 
Geiger Cape,00A0,Geiger Inc,
 
  
 
(start running)
 
(start running)
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538004
 
538004
 
</pre>
 
</pre>
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 +
=== Hardware ===
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====  Tubes Tested ====
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'''NOTE:''' These values may change if inductor on future revs is different.
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{|  border="1" cellspacing="0" cellpadding="4"
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|- bgcolor="#c0e0e0"
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| '''Name'''
 +
| '''Status'''
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| '''Duty Percent @ 20kHz'''
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|-
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| LND-712
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| Passed
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| align="right" | 60%
 +
|-
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| SBM-20
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| Passed
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| align="right" |40%
 +
|}
  
 
== Multimedia ==
 
== Multimedia ==
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<references>
 
<references>
<ref name="kernel_tree"> [https://github.com/beagleboard/kernel Beaglebone.org GitHub tree]
+
<ref name="kernel_tree"> [https://github.com/beagleboard/kernel Beaglebone.org GitHub tree] </ref>
 +
<ref name="cape_winner"> [http://beagleboard.org/CapeContest/entries/ Beagleboard.org Cape Contest Winners] </ref>
 
</references>
 
</references>

Revision as of 21:44, 4 February 2013

Introduction

Name Role
Matt Ranostay Backup HW design/Userspace applications/Presenter
Dimitris Sapountzakis HW design
Pantelis Antoniou Cape Manager + DT overlay support

Winner of Beagleboard.org Cape Contest [1]

Design

The Geiger uses a simple circuit design (see references for schematic) and LND-712 tube but the magic is everything is an extension of Beaglebone + AM335x chip:

  • PWM controls the boost converter
  • Analog (AIN) feedback reports back current voltage of boost converter
  • GPIO interrupts for radiations events

Future design work (some in progress):

  • Fix current limiter with op-amps
  • Use resistors that are within spec
  • eCAP support to reduce the need of the pulse extender part of PCB, using a small ceramic capacitor versus 1 uF electrolytic one, and which in turn will reduce "dead time".

Software

Geiger Cape kernel support is available in Beagleboard.org GitHub tree[2]. There are demo applications available in the links below.

Communication with the cape is using Pantelis Antoniou's Capemanager + DT overlays driver interface (example output below):

Confirm Cape Manager picked up device
	# cd /sys/devices/ocp.2/bone-cape-geiger.11

	(start running)
	# echo 1 > run

	(power LED turns on and the event LED lights up on a “click”)

Display counts:
	# cat counter
	4344

Display VSENSE (voltage feedback loop) in Millivolts:
	# cat vsense
	538004

Hardware

Tubes Tested

NOTE: These values may change if inductor on future revs is different.

Name Status Duty Percent @ 20kHz
LND-712 Passed 60%
SBM-20 Passed 40%

Multimedia

ELCE 2012 Demo Picture
Video Links
Geiger Cape Sample App
CapeBus + Geiger Cape

ELC Europe 2012 Presentation

Matt Ranostay Beaglebone: The Perfect Telemetry Platform? PDF


Samples X11 + Python demo scripts + Schematic design:

Beaglebone Telemetry Presentation Resources