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Mike Harsch mharsch

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  • Broomfield, CO
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@mharsch
mharsch / gist:5542211
Created May 8, 2013 17:53
raspbian config for unsecured ad-hoc wifi using edimax EW-7811UN usb wifi adapter 8192cu driver
pi@raspberrypi ~ $ cat /etc/network/interfaces
auto lo
iface lo inet loopback
iface eth0 inet dhcp
allow-hotplug wlan0
iface wlan0 inet static
address 10.0.0.1
netmask 255.0.0.0
@mharsch
mharsch / gist:5645674
Created May 24, 2013 18:47
generate list for ffmpeg concat
ls *.flv | awk '{ print "file '\''"$1"'\''" }'
@mharsch
mharsch / gist:5943801
Last active April 18, 2018 11:38
Roomba power supply + serial interface for Raspberry Pi

Roomba exposes both unregulated battery voltage (+14v, GND), and a 5v TTL serial interface via it's mini-din connector. Also exposed is an active-low signal pin called DD (Device Detect) that can be used to wakeup a sleeping/off Roomba.

Rpi has a 3.3v TTL serial interface exposed on it's header pins. Also, Rpi exposes +5v, +3.3v, GND, as well as GPIO pins.

We can leverage the Roomba battery to power the Rpi by adding a voltage regulator circuit between the roomba min-din battery pins and the 5v/GND power pins on the Rpi header. I've chosen the following part from the RC community (called a UBEC Universal Battery Elimination Circuit) to power the Rpi: this or this

To convert the 5v Roomba signals (both serial and DD) to/from 3.3v, I've chosen this:

@mharsch
mharsch / gist:6050888
Last active December 20, 2015 01:39
Notes for final nodebots day organizer's meeting:
Chris will record his intro video and give to dshaw before Thursday
length will be 20min max
content will include 'get to blinking led' bootstrap sequence
dshaw recommends following up with all attendees this week to combat attrition
Medellín is considering streaming video toward the end of their event
@mharsch
mharsch / VSpeedTeleOp.java
Created September 12, 2015 19:10
PRA's FTC TeleOp V1
package com.qualcomm.ftcrobotcontroller.opmodes;
import com.qualcomm.robotcore.eventloop.opmode.OpMode;
import com.qualcomm.robotcore.hardware.DcMotor;
import com.qualcomm.robotcore.util.Range;
/**
* Created by mharsch on 9/12/15.
*/
public class VSpeedTeleOp extends OpMode {
@mharsch
mharsch / gist:7f2a9b06d4b3291cea67847819d2e2d8
Last active December 29, 2022 23:46
Notes on ConnectedIO LTE modem + Raspberry Pi
The following applies to using the ConnectedIO LT1001 and LT1002 LTE modems on Verizon
in North America with the Raspberry Pi running Raspbian Jessie Lite (04/10/2017).
These guidelines assume that the modem interface will be the primary connection to
the Internet under normal conditions (i.e. not initial setup or field servicing).
Initial Setup
Establish serial communications with the modem (e.g. minicom -D /dev/ttyACM0).
Check modem firmware version with AT%VER and decide if you want/need to upgrade.
@mharsch
mharsch / gist:3fad6a10ca627823a7963bbb13831656
Created September 6, 2018 00:10
FTC OnBot Java using Atom editor
Enjoy lighting fast build turnaround time (provided by OnBot Java) without sacrificing a nice (local) development environment.
1.) Install Atom from atom.io
2.) within atom, install the 'build' package (https://atom.io/packages/build)
3.) Install ftc_http per the instructions for your platform (https://github.com/TheLostLambda/ftc_http)
3.a) Review the ftc_http documentation and watch the video (https://youtu.be/gZabYO8g9mU)
4.) Create a new directory for your opmode code. Inside this directory, create a file called '.atom-build.js'
Contents of .atom-build.js
@mharsch
mharsch / gist:30f5262b0a6fb634c2d0bf6d0836c430
Last active July 29, 2020 16:34
setup ethereum mining on ubuntu 18.04 with polaris card
1.) install ubuntu 18.04.2 server edition from usb
2.) run sudo apt update && sudo apt dist-upgrade
3.) download latest linux drivers from amd (e.g. amdgpu-pro-19.10-785425-ubuntu-18.04.tar.xz)
4.) install drivers with './amdgpu-pro-install -y --opencl=pal,legacy --headless
5.) add /opt/amdgpu-pro/bin to your path. Test opencl with 'sudo /opt/amdgpu-pro/bin/clinfo'
6.) add rocm apt source
wget -qO - http://repo.radeon.com/rocm/apt/debian/rocm.gpg.key | sudo apt-key add -
echo 'deb [arch=amd64] http://repo.radeon.com/rocm/apt/debian/ xenial main' | sudo tee /etc/apt/sources.list.d/rocm.list
7.) install rocm-smi package
8.) add the following parameter to the /etc/default/grub file on the GRUB_CMDLINE_LINUX_DEFAULT line: amdgpu.ppfeaturemask=0xffffffff
@mharsch
mharsch / moto e5 go verizon prepaid unlock
Created September 27, 2019 14:42
break out of initial activation jail on Verizon moto e5 go prepaid phones ($30 at BestBuy -- subsidized price)
Boot phone and attempt activation -- fails
tap screen 5 times to go into QR code setup mode -- configure wifi
restart phone
attempt activation -- fails, wifi is still connected from before
attempt a few more times -- fails each time
go back into QR code setup mode and enter wrong wifi password for your network (breaking wifi)
phone now shows 4GLTE status
attempt activation -- fails but allows you to continue with wifi -- reconfigure wifi and move on.
@mharsch
mharsch / gist:c3e3c5b69251ab05e208641b0e3c249b
Last active March 19, 2020 19:16
nvidia headless opencl ubuntu 18.04 setup in 2020
Install latest 18.04 (server) version
apt install software-properties-common
add-apt-repository ppa:graphics-drivers
apt install nvidia-headless-440
apt install nvidia-utils-440
apt install nvidia-opencl-dev //all of this just to get a symlink for libOpenCL.so
# see discussion of the above issue here: https://foldingforum.org/viewtopic.php?f=106&t=30836&start=15#p313509
# workaround: create the following symlink (this let's you skip the whole nvidia-opencl-dev package):
lrwxrwxrwx 1 root root 18 Mar 19 13:10 /usr/lib/x86_64-linux-gnu/libOpenCL.so -> libOpenCL.so.1.0.0