Thursday, 28 December 2017

Print a Range of a char Array without a for Loop

Code:
#include <stdio.h> 
 int main() 
   char a[1024] = "abcdefghijklmnopqrstuvwxyz";  
   printf("Characters 0 through 2 of a[]: %.3s\n", a); 
   printf("Characters 10 through 15 of a[]: %.6s\n", &a[10]); return 0; 
}

Prints this:
Characters 0 through 2 of a[]: abc 
Characters 10 through 15 of a[]: klmnop

The "%.Ns" notation in the printf string is "%s" with a precision specifier. It's buried in the geek-speak in the printf(3) man page


ref:
https://www.linuxquestions.org/questions/programming-9/is-there-a-way-to-print-a-range-of-a-char-array-without-a-for-loop-842798/

Tuesday, 26 December 2017

Arduino Command Line Usage


arduino is simply a program from your installation directory. Without any parameters, it would just start the Arduino IDE.

open ~/.bashrc and add the following line at the bottom:
              PATH=$PATH:/home/aaa/xxx/yyy/arduinoIDE/arduino-1.8.2
Now we can use cmd "arduino" everywhere.

Use cases:
For arduino nano:
arduino --board arduino:avr:nano:cpu=atmega328 --port /dev/ttyUSB0 --upload beep.ino

Serial Monitor:
picocom /dev/ttyUSB0 -b 9600

ref:
https://unix.stackexchange.com/questions/26047/how-to-correctly-add-a-path-to-path
https://github.com/arduino/Arduino/blob/master/build/shared/manpage.adoc

Tuesday, 19 December 2017

I think the following problems are the same:

Problem 1:
E: Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable)
E: Unable to lock the administration directory (/var/lib/dpkg/), is another process using it?


Problem  2:
sudo apt-get -f install
Reading package lists... Done
Building dependency tree       
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 39 not upgraded.
5 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Setting up linux-image-extra-4.4.0-104-generic (4.4.0-104.127) ...
run-parts: executing /etc/kernel/postinst.d/apt-auto-removal 4.4.0-104-generic /boot/vmlinuz-4.4.0-104-generic
run-parts: executing /etc/kernel/postinst.d/initramfs-tools 4.4.0-104-generic /boot/vmlinuz-4.4.0-104-generic
update-initramfs: Generating /boot/initrd.img-4.4.0-104-generic

gzip: stdout: No space left on device
E: mkinitramfs failure cpio 141 gzip 1
update-initramfs: failed for /boot/initrd.img-4.4.0-104-generic with 1.
run-parts: /etc/kernel/postinst.d/initramfs-tools exited with return code 1
dpkg: error processing package linux-image-extra-4.4.0-104-generic (--configure):
 subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of linux-image-generic:
 linux-image-generic depends on linux-image-extra-4.4.0-104-generic; however:
  Package linux-image-extra-4.4.0-104-generic is not configured yet.

dpkg: error processing package linux-image-generic (--configure):
 dependency problems - leaving unconfigured
dpkg: dependency problems prevent configuration of linux-generic:
 linux-generic depends on linux-image-generic (= 4.4.0.104.109); however:
  Package linux-image-generic is not configured yet.

dpkg: error processing package linux-generic (--configure):
 dependency problems - leaving unconfigured
Setting up linux-image-4.4.0-98-generic (4.4.0-98.121) ...
No apport report written because the error message indicates its a followup error from a previous failure.
                                                                                                          No apport report written because the error message indicates its a followup error from a previous failure.
                                                                             Running depmod.
update-initramfs: deferring update (hook will be called later)
The link /initrd.img is a dangling linkto /boot/initrd.img-4.4.0-98-generic
vmlinuz(/boot/vmlinuz-4.4.0-98-generic
) points to /boot/vmlinuz-4.4.0-98-generic
 (/boot/vmlinuz-4.4.0-98-generic) -- doing nothing at /var/lib/dpkg/info/linux-image-4.4.0-98-generic.postinst line 491.
Examining /etc/kernel/postinst.d.
run-parts: executing /etc/kernel/postinst.d/apt-auto-removal 4.4.0-98-generic /boot/vmlinuz-4.4.0-98-generic
run-parts: executing /etc/kernel/postinst.d/initramfs-tools 4.4.0-98-generic /boot/vmlinuz-4.4.0-98-generic
update-initramfs: Generating /boot/initrd.img-4.4.0-98-generic

gzip: stdout: No space left on device
E: mkinitramfs failure cpio 141 gzip 1
update-initramfs: failed for /boot/initrd.img-4.4.0-98-generic with 1.
run-parts: /etc/kernel/postinst.d/initramfs-tools exited with return code 1
Failed to process /etc/kernel/postinst.d at /var/lib/dpkg/info/linux-image-4.4.0-98-generic.postinst line 1052.
dpkg: error processing package linux-image-4.4.0-98-generic (--configure):
 subprocess installed post-installation script returned error exit status 2
No apport report written because MaxReports is reached already
                                                              dpkg: dependency problems prevent configuration of linux-image-extra-4.4.0-98-generic:
 linux-image-extra-4.4.0-98-generic depends on linux-image-4.4.0-98-generic; however:
  Package linux-image-4.4.0-98-generic is not configured yet.

dpkg: error processing package linux-image-extra-4.4.0-98-generic (--configure):
 dependency problems - leaving unconfigured
No apport report written because MaxReports is reached already
                                                              Errors were encountered while processing:
 linux-image-extra-4.4.0-104-generic
 linux-image-generic
 linux-generic
 linux-image-4.4.0-98-generic
 linux-image-extra-4.4.0-98-generic
E: Sub-process /usr/bin/dpkg returned an error code (1)

Problem  3:
The volume "boot" has only  bytes disk space remaining

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////
Solution:

Step 1:
List all the current existing kernels.

ls /boot/ | grep vmlinuz
vmlinuz-4.4.0-104-generic
vmlinuz-4.4.0-97-generic
vmlinuz-4.4.0-98-generic

Step 2:
Find the current kernel in use.

uname -r
4.4.0-97-generic

Step 3:
Remove one of them not in use:

sudo apt-get purge linux-image-4.4.0-104-generic
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following packages were automatically installed and are no longer required:
  linux-headers-4.4.0-104 linux-headers-4.4.0-104-generic linux-headers-generic thermald
Use 'sudo apt autoremove' to remove them.
0 upgraded, 0 newly installed, 0 to remove and 39 not upgraded.



ref:
https://askubuntu.com/questions/218783/the-volume-boot-has-only-0-bytes-disk-space-remaining


Thursday, 7 December 2017

Toubleshooting: ampy "could not enter raw repl" error


When using ampy tool, nothing works!

ampy --port /dev/ttyUSB0 get boot.py

>>> 
Traceback (most recent call last):
  File "/usr/local/bin/ampy", line 11, in <module>
    sys.exit(cli())
  File "/usr/local/lib/python2.7/dist-packages/click/core.py", line 722, in __call__
    return self.main(*args, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/click/core.py", line 697, in main
    rv = self.invoke(ctx)
  File "/usr/local/lib/python2.7/dist-packages/click/core.py", line 1066, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/usr/local/lib/python2.7/dist-packages/click/core.py", line 895, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/usr/local/lib/python2.7/dist-packages/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/ampy/cli.py", line 96, in get
    contents = board_files.get(remote_file)
  File "/usr/local/lib/python2.7/dist-packages/ampy/files.py", line 68, in get
    self._pyboard.enter_raw_repl()
  File "/usr/local/lib/python2.7/dist-packages/ampy/pyboard.py", line 184, in enter_raw_repl
    raise PyboardError('could not enter raw repl')
ampy.pyboard.PyboardError: could not enter raw repl

On the NodeMCU side it prints:
...
>>>
>raw REPL; CTRL-B to exit >

The reason is because the serial port is busy. So after I closed the REPL python terminal and called ampy again, every thing works perfectly. 


ref:
http://forums.openmv.io/viewtopic.php?t=298

Casting Bitwise struct to Integer

I have bitwise structure with a bunch of flags.

struct {
  uint8_t a: 4; 
  uint8_t b: 4; 
} _tVarA

_tVarA Var_A = {0,0};

But when I want to view them as a whole integer, I need to cast it like this:
                               *(uint8_t*)&Var_A

ref:
http://www.avrfreaks.net/forum/casting-bitfield-struct-integer
https://stackoverflow.com/questions/11903820/casting-struct-into-int

Tuesday, 5 December 2017

Programming ESP8266 (01) using FTDI and Arduino IDE

ESP8266 is essentially a microcontroller. We can do development to it from the Arduino IDE.

Step 1: Install the ESP8266 board in Arduino IDE

According to the first method from https://github.com/esp8266/Arduino

(1) Start Arduino and open Preferences window.
(2) Enter http://arduino.esp8266.com/stable/package_esp8266com_index.json into Additional Board Manager URLsfield. You can add multiple URLs, separating them with commas.
(3) Open Boards Manager from Tools > Board menu and install esp8266 platform (and don't forget to select your ESP8266 board from Tools > Board menu after installation).









Step 2: Wiring
The Wiring is 90% the same from my last post: Getting Started with esp8266-01 as shown below:


The only thing different is that we must connect GND from FTDI to GPIO0 on ESP8266. This is to set the ESP8266 into "bootloading" mode. RST and GPIO2 pins can be left floating.







Step 3: Coding
If the board is chosen from Tool > Board as General ESP8266, we can just pull the blinky example from File > examples.


Step 4: Flash the Module

Flash the board using the following parameters.
/////////////////////////////////////////////////////////////////////////////////////////////

Troubleshooting:
(1)
At first I got the following error message:

warning: espcomm_sync failed
error: espcomm_open failed
error: espcomm_upload_mem failed
error: espcomm_upload_mem failed


Checked online and find some hints. The cause can be one of two things:

(1) Insufficient power. Try to power the ESP8266 from an external 3.3V power supply such as a lab supply. Two fully charged AA batteries should do the trick too. Make sure your serial adapter's GND pin is also connected to the ESP's GND pin in order to provide a common ground.

(2) ESP8266 is not in programming mode. Make sure GPIO0 is attached to GND and turn the ESP off and on again. It will then boot into programming mode. Once programmed, you can take it off GND.
So here is what I did:

> unplug the GND <=> GPIO0
basically go back the the getting start with ESP8266 post and do "AT" command and got "OK".

> plug the GND <=> GPIO0 back again
Flash and it worked!! You can see the blue led blinking.


(2)
Next day, I plug in the ftdi and the blue is NOT blinking any more. We must put it back to normal mode by unplug the GPIO0 from GND.


ref:
https://www.monocilindro.com/2017/02/25/flashing-esp8266-using-ftdi-and-arduino-ide/
https://github.com/esp8266/Arduino
https://stackoverflow.com/questions/31371969/cannot-program-esp8266

Monday, 4 December 2017

Getting Started with the ESP8266 (01)

Step 1: Wiring

I got a ESP-01 version of this module, which has 8 pins: VCC, GND, CH_PD, TX, RX, RST, GPIO0, and GPIO1. Wiring the module is not complicated and should be the same for all versions of this module:

  • VCC needs 3.3V
  • CH_PD has to be pulled-up (meaning it has to be connected to 3.3V as well)
  • GND is connected to FTDI’s GND pin
  • RX is connected to FTDI’s TX pin, because you want to create a loop: RX-> TX => RX -> TX
  • TX is connected to FTDI’s RX pin
  • other pins are left floating

VERY VERY IMPORTANTLY, this module needs 3.3V, not 5V which is what most FTDIs supply. Even if your FTDI module has an 3.3V output or a switch to change the voltage, please measure it with a multimeter to make sure it is outputing 3.3V exactly. I wasted more than one hour just because I trusted the piece of garbage!!!!

Step 2: Communication


Open the serial monitor from Arduino IDE, change the two settings at the right bottom corner according to the above picture. As you can see, my first 3 AT command didn't go through because of the carriage return is not there.


ref:
http://williamdurand.fr/2015/03/17/playing-with-a-esp8266-wifi-module/
http://rancidbacon.com/files/kiwicon8/ESP8266_WiFi_Module_Quick_Start_Guide_v_1.0.4.pdf
http://www.instructables.com/id/Getting-Started-With-the-ESP8266-ESP-01/

STATIC Variables and Functions in C




ref:
http://www.jianshu.com/p/f413ba3b2728
http://www.cnblogs.com/wly603/archive/2012/04/11/2442065.html
http://bbs.csdn.net/topics/350238100
http://www.cppblog.com/dbkong/archive/2006/12/09/16169.html

Build MicroPython Firmware for ESP8266





ref:
https://learn.adafruit.com/building-and-running-micropython-on-the-esp8266/build-firmware
https://github.com/micropython/micropython/wiki/Getting-Started

Friday, 24 November 2017

Create your Own I2C module

If you have a daughter system, for example sensor(s), and you need to talk to it from the master MCU, you can of course use CAN bus. But you can also turn it into an I2C module.

ref:
http://www.instructables.com/id/I2C-between-Arduinos/
http://dsscircuits.com/articles/arduino-i2c-slave-guide

Create a New Branch from a History Commit

When we want to checkout a new branch we do:

git checkout -b name-of-new-branch 

This is actually shorten for:

git checkout -b name-of-new-branch current-branch 

That is to say, if we don't specify the starting point of this new branch, it starts by default from the current active branch. Since every commit has an SHA1 (Hash value) as its ID, we can use these IDs as the start pointer when we are using checkout command. For example:

git checkout -b name-of-new-branch 169d2dc 

In this way, the active branch is now switched to this new branch and things are the same with branch 169d2dc.

Note that we might need to use the long full SHA1 ID in case the short one conflicts with others.


ref:
https://liam0205.me/2015/04/29/git-checkout-history-version/

Git Workflow for Embedded Systems

The special thing about embedded system is that it sits in between software and hardware. Therefore, you might hit walls if adopting the traditional git workflow. The following blog specified the obstacles really well:

https://medium.com/jumperiot/how-to-use-git-flow-in-embedded-software-development-dbb2a78da413

I met the problem of different hardware configurations and I have to go back to history versions to branch out and do some redundant work. But most importantly, keep the following three things in mind:

(1) Split the code base into unrelated libraries/modules that support different configurations, manage them separately and then do a configuration management. Note that you’ll need to invest in proper software architecture and abstraction layers.
(2) Control different configuration with features flags on the same branches.
(3) Create isolated and long lived branches for each version/hardware configuration.

ref:
https://medium.com/jumperiot/how-to-use-git-flow-in-embedded-software-development-dbb2a78da413
https://liam0205.me/2015/04/29/git-checkout-history-version/

Thursday, 23 November 2017

Producer Consumer Model in Python

All credits go to Akshar Raaj

Note that if Queue is used, queue itself is threading safe to use because Queue encapsulates the behaviour of Condition, wait(), notify(), acquire() etc.

ref:
http://agiliq.com/blog/2013/10/producer-consumer-problem-in-python/

Wednesday, 22 November 2017

Install Python 3 Packets

By default if you install something by
      pip install some_packet
I got the packet in Python 2.7 installed.

But if a packet, say pyusb, is a dependent to another packet that has be on Python 3, say pystlink, I will get:

Traceback (most recent call last):
  File "pystlink.py", line 4, in <module>
    import lib.stlinkusb
  File "/home/boris/Softwares/EmbeddedSystem/pystlink/pystlink-master/lib/stlinkusb.py", line 1, in <module>
    import usb.core
ImportError: No module named 'usb'

If I try to go to Python 3 and import usb, I would get the same output. Therefore, I need to install pyusb in Python 3 and here is how.

sudo apt-get install python3-pip
sudo pip3 install MODULE_NAME

ref:
https://stackoverflow.com/questions/10763440/how-to-install-python3-version-of-package-via-pip-on-ubuntu

Monday, 20 November 2017

UART Communication Between NodeMCU and Arduino

First, I'm using MicroPython on the NodeMCU side.

Test 1:
Connections:
VIN     -    VIN
GND   -    GND
3          -    D3
2          -    D2

Arduino side code:
#include <SoftwareSerial.h>
SoftwareSerial ArduinoSerial(3, 2); // RX, TX
void setup() 
{
  Serial.begin(115200);
  ArduinoSerial.begin(4800);
}

void loop() 
{
  ArduinoSerial.write('abc');
  delay(100);
}

NudeMCU side:
from machine import 
UART uart = UART(1, 4800) 
uart.init(4800, bits=8, parity=None, stop=1) 
uart.read()

And...it didn't work.





There is UART 0 that is connected to the usb-serial converter and runs the repl.
There is UART 1 that only has a TX pin so I cannot receive data.
OSError: UART(1) can't read
There is UART 2 that doesn't seem to exist in micropython.
ValueError: UART(2) does not exist

So be it...Then we have two choices:
(1) use UART 1 but only sending data from NodeMCU to Arduino -- Test 2
(2) use UART 0 but not use the USB. -- Test 3

Both of the above tests are done using Arduino after flashing program to NodeMCU.

Test 2:




Test 3:





ref:
https://www.arduinoall.com/article/59/nodemcu-esp8266-esp8285-arduino-30-esp8266-nodemcu-%E0%B8%95%E0%B8%B4%E0%B8%94%E0%B8%95%E0%B9%88%E0%B8%AD-arduino-%E0%B9%81%E0%B8%9A%E0%B8%9A-serial
https://www.arduino.cc/en/Reference/SoftwareSerial
https://www.arduino.cc/en/Tutorial/SoftwareSerialExample
https://docs.micropython.org/en/latest/esp8266/library/machine.UART.html?highlight=uart
https://github.com/micropython/micropython/issues/2391
https://github.com/esp8266/Arduino/issues/482

Thursday, 16 November 2017

MicroPython + NodeMCU Getting Started


(0) sudo pip install esptool
(1) esptool.py --port /dev/ttyUSB0 erase_flash

esptool.py v2.1
Connecting....
Detecting chip type... ESP8266
Chip is ESP8266
Uploading stub...
Running stub...
Stub running...
Erasing flash (this may take a while)...
Chip erase completed successfully in 7.8s
Hard resetting...

(2) esptool.py --port /dev/ttyUSB0 --baud 460800 write_flash --flash_size=detect 0 esp8266-20171101-v1.9.3.bin 

esptool.py v2.1
Connecting....
Detecting chip type... ESP8266
Chip is ESP8266
Uploading stub...
Running stub...
Stub running...
Changing baud rate to 460800
Changed.
Configuring flash size...
Auto-detected Flash size: 4MB
Flash params set to 0x0040
Compressed 600888 bytes to 392073...
Wrote 600888 bytes (392073 compressed) at 0x00000000 in 8.9 seconds (effective 542.3 kbit/s)...
Hash of data verified.

Leaving...
Hard resetting...

(3) picocom /dev/ttyUSB0 -b 115200

picocom v1.7

port is        : /dev/ttyUSB0
flowcontrol    : none
baudrate is    : 115200
parity is      : none
databits are   : 8
escape is      : C-a
local echo is  : no
noinit is      : no
noreset is     : no
nolock is      : no
send_cmd is    : sz -vv
receive_cmd is : rz -vv
imap is        : 
omap is        : 
emap is        : crcrlf,delbs,

Terminal ready

////////////////////////////////////////////////
I have to unplug and plug the USB back in. Resetting the device won't work. I got the following error message:

picocom v1.7

port is        : /dev/ttyUSB0
flowcontrol    : none
baudrate is    : 115200
parity is      : none
databits are   : 8
escape is      : C-a
local echo is  : no
noinit is      : no
noreset is     : no
nolock is      : no
send_cmd is    : sz -vv
receive_cmd is : rz -vv
imap is        : 
omap is        : 
emap is        : crcrlf,delbs,


FATAL: cannot open /dev/ttyUSB0: Device or resource busy

This could also be a bad usb cable. Use a good one with a data line on it.


///////////////////////////////////////////////////
///////////////////////////////////////////////////
///////////////////////////////////////////////////
Also you might need to press enter a few times to see the Python prompt:

.......
imap is        : 
omap is        : 
emap is        : crcrlf,delbs,

Terminal ready

>>> 
>>> 
>>> 

(4) Start playing around
Hookup an LED on D7 which is mapped to GPIO13.

>>> import machine
>>> pin = machine.Pin(13, machine.Pin.OUT)
>>> pin.on()
>>> pin.off()

You can see the LED goes on and off now. Happy tinkering!


ref:
https://docs.micropython.org/en/latest/esp8266/esp8266/tutorial/intro.html
https://dev.to/kenwalger/micropython-and-the-nodemcu-esp8266
http://www.instructables.com/id/MicroPython-Basics-Using-NodeMCU-ESP8266/
https://hackaday.com/2016/07/21/micropython-on-the-esp8266-kicking-the-tires/

Wednesday, 15 November 2017

Getting Started with NodeMCU

Many suggest to install different kind of drivers. But I thought would at least see that list in dmesg.
But the first reference woke me up with some similar problems I met.

USE A BETTER/DIFFERENT USB CABLE!!!!

ref:
http://www.esp8266.com/viewtopic.php?f=13&t=4366
https://www.silabs.com/products/development-tools/software/usb-to-uart-bridge-vcp-drivers
https://www.marginallyclever.com/2017/02/setup-nodemcu-drivers-arduino-ide/
https://github.com/nodemcu/nodemcu-devkit/blob/master/Drivers/CH341SER_LINUX.ZIP
http://mohanp.com/nodemcu-esp8266-with-adruino-ide/

Monday, 6 November 2017

System Panic in Particle System (STM32)



particle System Panic reset reason 130

ref:
https://community.particle.io/t/photon-system-panic-hard-fault-task-stack-size/30758
https://community.particle.io/t/core-firmware-sos-panic-codes/4337/5

Monday, 30 October 2017

Manage Startup Applications in Ubuntu

Ubuntu has an GUI called Startup Applications.

ref:
https://linux.cn/article-5943-1.html

Wednesday, 18 October 2017

You really count on using things like GitKraken in the Server? Git itself is powerful enough:

git log --graph --full-history --all --color \
        --pretty=format:"%x1b[31m%h%x09%x1b[32m%d%x1b[0m%x20%s"
ref:
https://stackoverflow.com/questions/1838873/visualizing-branch-topology-in-git


Tuesday, 19 September 2017

Particle Installation Troubleshooting

If you see such things like:

node-pre-gyp ERR! Pre-built binaries not found for serialport@4.0.7 and node@4.2.1 (node-v46 ABI) (falling back to source compile with node-gyp)
gyp WARN EACCES user "root" does not have permission to access the dev dir "/root/.node-gyp/4.2.1"
gyp WARN EACCES attempting to reinstall using temporary dev dir "/usr/local/lib/node_modules/particle-cli/node_modules/serialport/.node-gyp"
make: Entering directory '/usr/local/lib/node_modules/particle-cli/node_modules/serialport/build'
make: *** No rule to make target '../.node-gyp/4.2.1/include/node/common.gypi', needed by 'Makefile'. Stop.
make: Leaving directory '/usr/local/lib/node_modules/particle-cli/node_modules/serialport/build'
gyp ERR! build error
gyp ERR! stack Error: make failed with exit code: 2
gyp ERR! stack at ChildProcess.onExit (/usr/local/lib/node_modules/npm/node_modules/node-gyp/lib/build.js:270:23)
gyp ERR! stack at emitTwo (events.js:87:13)
gyp ERR! stack at ChildProcess.emit (events.js:172:7)
gyp ERR! stack at Process.ChildProcess.handle.onexit (internal/childprocess.js:200:12)
gyp ERR! System Linux 4.9.24+
gyp ERR! command "/usr/local/bin/node" "/usr/local/lib/node_modules/npm/node_modules/node-gyp/bin/node-gyp.js" "build" "--fallback-to-build" "--module=/usr/local/lib/node_modules/particle-cli/node_modules/serialport/build/Release/serialport.node" "--module_name=serialport" "--module_path=/usr/local/lib/node_modules/particle-cli/node_modules/serialport/build/Release"
gyp ERR! cwd /usr/local/lib/node_modules/particle-cli/node_modules/serialport
gyp ERR! node -v v4.2.1
gyp ERR! node-gyp -v v3.0.3
gyp ERR! not ok
node-pre-gyp ERR! build error
node-pre-gyp ERR! stack Error: Failed to execute '/usr/local/bin/node /usr/local/lib/node_modules/npm/node_modules/node-gyp/bin/node-gyp.js build --fallback-to-build --module=/usr/local/lib/node_modules/particle-cli/node_modules/serialport/build/Release/serialport.node --module_name=serialport --module_path=/usr/local/lib/node_modules/particle-cli/node_modules/serialport/build/Release' (1)
node-pre-gyp ERR! stack at ChildProcess. (/usr/local/lib/node_modules/particle-cli/node_modules/serialport/node_modules/node-pre-gyp/lib/util/compile.js:83:29)
node-pre-gyp ERR! stack at emitTwo (events.js:87:13)
node-pre-gyp ERR! stack at ChildProcess.emit (events.js:172:7)
node-pre-gyp ERR! stack at maybeClose (internal/child_process.js:818:16)
node-pre-gyp ERR! stack at Process.ChildProcess.handle.onexit (internal/childprocess.js:211:5)
node-pre-gyp ERR! System Linux 4.9.24+
node-pre-gyp ERR! command "/usr/local/bin/node" "/usr/local/lib/node_modules/particle-cli/node_modules/serialport/node_modules/.bin/node-pre-gyp" "install" "--fallback-to-build"
node-pre-gyp ERR! cwd /usr/local/lib/node_modules/particle-cli/node_modules/serialport
node-pre-gyp ERR! node -v v4.2.1
node-pre-gyp ERR! node-pre-gyp -v v0.6.32
node-pre-gyp ERR! not ok
Failed to execute '/usr/local/bin/node /usr/local/lib/node_modules/npm/node_modules/node-gyp/bin/node-gyp.js build --fallback-to-build --module=/usr/local/lib/node_modules/particle-cli/node_modules/serialport/build/Release/serialport.node --module_name=serialport --module_path=/usr/local/lib/node_modules/particle-cli/node_modules/serialport/build/Release' (1)
npm ERR! Linux 4.9.24+
npm ERR! argv "/usr/local/bin/node" "/usr/local/bin/npm" "install" "-g" "particle-cli"
npm ERR! node v4.2.1
npm ERR! npm v2.14.7
npm ERR! code ELIFECYCLE
npm ERR! serialport@4.0.7 install: node-pre-gyp install --fallback-to-build
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the serialport@4.0.7 install script 'node-pre-gyp install --fallback-to-build'.
npm ERR! This is most likely a problem with the serialport package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR! node-pre-gyp install --fallback-to-build
npm ERR! You can get their info via:
npm ERR! npm owner ls serialport
npm ERR! There is likely additional logging output above.
npm ERR! Please include the following file with any support request:
npm ERR! /home/pi/npm-debug.log


This is a known but relatively undocumented bug with the particle-cli installation process. The following should work:

           $ sudo npm install -g --unsafe-perm node-pre-gyp npm serialport particle-cli

ref:
https://community.particle.io/t/connecting-particle-photon-to-local-server-on-raspberry-pi-zero-w/32227
https://community.particle.io/t/new-cli-on-os-x-10-11-el-capitan-solved/28802/8



Sunday, 17 September 2017

"The volume "boot" has only 0 bytes disk space remaining" error

Very simple

sudo apt-get autoremove

This will delete those unuseful kernels in /boot.

ref:
https://ubuntuforums.org/showthread.php?t=2239126
https://askubuntu.com/questions/345588/what-is-the-safest-way-to-clean-up-boot-partition

Thursday, 7 September 2017

Setting up GCC ARM Coding Environment for STMicrocontroller


1. Installing compiler and stlink

To compile C and/or C++ source code of your firmware you will need gcc-arm-none-eabi compiler and stlink.

Installing gcc-arm-none-eabi

What is extremely useful, there are complete and easy to install packages for all major platforms (https://launchpad.net/~team-gcc-arm-embedded/+archive/ubuntu/ppa)
sudo add-apt-repository ppa:team-gcc-arm-embedded/ppa
sudo apt-get update
sudo apt-get install gcc-arm-none-eabi

Installing stlink

At first, we need install dependencies then build it from sources (https://github.com/texane/stlink/blob/master/doc/compiling.md#build-from-sources).
sudo apt-get install git build-essential libusb-1.0.0-dev cmake
cd $HOME
git clone git@github.com:texane/stlink.git
cd stlink
make release
cd build/Release && make install DESTDIR=_install
echo "export PATH=\$PATH:$HOME/stlink/build/Release/_install/usr/local/bin" >> $HOME/.bashrc

2. Compiling and burning the code

Now that you have the toolchain installed, a next step is to compile the source code into a .ELF, then generate .BIN file and finally burn this this binary file to STM32 chip using ST-Link v2 programmer.

Example code

Here is an example content of main.c file. The code does nothing except getting stuck in an endless loop but it’s always something!
int
main(void)
{

        while (1);
}

Compiling

The command below will compile your code. It’s GCC so I assume it looks familiar to you and no additional explanations are needed. If you want perform compilation for some other MCU then you need specify at least appropriate -mcpu, .LD and .S files (not provided in this tutorial)
$ arm-none-eabi-gcc -std=gnu99 -g -O2 -Wall -mlittle-endian -mthumb -mthumb-interwork -mcpu=cortex-m0 -fsingle-precision-constant -Wdouble-promotion main.c -o main.elf
After performing successful compilation, you can check program and data memory size with this command.
$ arm-none-eabi-size -tA main.elf 
main.elf  :
section              size        addr
.isr_vector           192   134217728
.text                6404   134217920
.rodata                60   134224324
.ARM                    8   134224384
.init_array             8   134224392
.fini_array             4   134224400
.data                1092   536870912
.jcr                    4   536872004
.bss                   32   536872008
._user_heap_stack    1536   536872040
.ARM.attributes        40           0
.comment               31           0
.debug_line          7416           0
.debug_info         22917           0
.debug_abbrev        6837           0
.debug_aranges        744           0
.debug_loc           6584           0
.debug_ranges         472           0
.debug_str           5717           0
.debug_frame         2004           0
Total               62102

Generating .BIN

Most programmers will not accept a GNU executable as an input file, so we need to do a little more processing. So, the next step is about converting the information form .ELF into .BIN file. The GNU utility that does this is called arm-none-eabi-objcopy.
$ arm-none-eabi-objcopy -O binary main.elf main.bin

Burning

The utility called st-flash can program processors using the content of the .BIN files specified on the command line. With the command below, the file main.bin will be burned into the flash memory.
$ st-flash write main.bin 0x8000000
Voila! Chip is programmed.

3. Make and Makefiles

Now, we can automate this process by creating a Makefile and putting our commands there. The structure of a Makefile is very simple, and more information about it can be found here. Utility make reads automatically a Makefile file in the folder where you launch it. Take a look at simple Makefile presented bellow.
TARGET=main

CC=arm-none-eabi-gcc
LD=arm-none-eabi-gcc
AR=arm-none-eabi-ar
AS=arm-none-eabi-as
CP=arm-none-eabi-objcopy
OD=arm-none-eabi-objdump
SE=arm-none-eabi-size
SF=st-flash

CFLAGS  = -std=gnu99 -g -O2 -Wall
CFLAGS += -mlittle-endian -mthumb -mthumb-interwork -mcpu=cortex-m0
CFLAGS += -fsingle-precision-constant -Wdouble-promotion

SRCS =  main.c

.PHONY: $(TARGET)

$(TARGET): $(TARGET).elf

$(TARGET).elf: $(SRCS)
        $(CC) $(INCLUDE) $(CFLAGS) $^ -o $@
        $(CP) -O binary $(TARGET).elf $(TARGET).bin

clean:
        rm -f *.o $(TARGET).elf $(TARGET).bin

flash:
        $(SF) write $(TARGET).bin 0x8000000
If you launch a simple make in the terminal, only label “all” will be executed. When you launch make flash label “flash” will be executed, and so on.

4. Summary

Essentially, assuming that our program is in main.c, only those three things are needed to compile and burn the code to STM32 chip.
$ arm-none-eabi-gcc -std=gnu99 -g -O2 -Wall -mlittle-endian -mthumb -mthumb-interwork -mcpu=cortex-m0 -fsingle-precision-constant -Wdouble-promotion main.c -o main.elf
$ arm-none-eabi-objcopy -O binary main.elf main.bin
$ st-flash write main.bin 0x8000000


It’s important to highlight that we can easily automate whole process with Makefiles. Sooner or later you will need it!



ref:
http://blog.podkalicki.com/how-to-compile-and-burn-the-code-to-stm32-chip-on-linux-ubuntu/
https://startingelectronics.org/tutorials/STM32-microcontrollers/programming-STM32-flash-in-Linux/
http://fishpepper.de/2016/09/16/installing-using-st-link-v2-to-flash-stm32-on-linux/

Tuesday, 5 September 2017

The Django Book Study -- Installing Django

I stucked a bit at this part:

To use this new Python virtual environment, we have to activate it, so let’s go back to the command prompt and type the following:
env_mysite\scripts\activate
This will run the activate script inside your virtual environment’s \scripts folder. You will notice your command prompt has now changed:
(env_mysite) C:\Users\Nigel\OneDrive\Documents\mysite_project>
The (env_mysite) at the beginning of the command prompt lets you know that you are running in the virtual environment. Our next step is to install Django.
Apparently, this is how it goes in Windows. In Linux, we would have to do the following:
source bin/activate
And then we can see:
boris@boris-D630:~/workspace/mysite_project/env_mysite$ source bin/activate
(env_mysite)boris@boris-D630:~/workspace/mysite_project/env_mysite$


ref:
https://pypi.python.org/pypi/virtualenv/1.8.2

Monday, 7 August 2017

dpkg: error processing package linux-image-generic (--configure): dependency problems - leaving unconfigured

I was installing ffmpeg the other day and something seems failed to be installed. I thought ffmpeg was not successfully installed but it actually DID!! I did it again and again. Everytime I'm getting error messages:

Reading package lists... Done
Building dependency tree       
Reading state information... Done
ffmpeg is already the newest version (7:3.3.3-1ubuntu1~16.04.york0).
The following packages were automatically installed and are no longer required:
  linux-headers-4.4.0-72 linux-headers-4.4.0-72-generic linux-image-4.4.0-72-generic linux-image-extra-4.4.0-72-generic
Use 'sudo apt autoremove' to remove them.
0 upgraded, 0 newly installed, 0 to remove and 277 not upgraded.
3 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n] Y
Setting up linux-image-extra-4.4.0-89-generic (4.4.0-89.112) ...
run-parts: executing /etc/kernel/postinst.d/apt-auto-removal 4.4.0-89-generic /boot/vmlinuz-4.4.0-89-generic
run-parts: executing /etc/kernel/postinst.d/initramfs-tools 4.4.0-89-generic /boot/vmlinuz-4.4.0-89-generic
update-initramfs: Generating /boot/initrd.img-4.4.0-89-generic

gzip: stdout: No space left on device
E: mkinitramfs failure cpio 141 gzip 1
update-initramfs: failed for /boot/initrd.img-4.4.0-89-generic with 1.
run-parts: /etc/kernel/postinst.d/initramfs-tools exited with return code 1
dpkg: error processing package linux-image-extra-4.4.0-89-generic (--configure):
 subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of linux-image-generic:
 linux-image-generic depends on linux-image-extra-4.4.0-89-generic; however:
  Package linux-image-extra-4.4.0-89-generic is not configured yet.

dpkg: error processing package linux-image-generic (--configure):
 dependency problems - leaving unconfigured
dpkg: dependency problems prevent configuration of linux-generic:
 linux-generic depends on linux-image-generic (= 4.4.0.89.95); however:
  Package linux-image-generic is not configured yet.

dpkg: error processing package linux-generic (--configure):
 dependency problems - leaving unconfigured
No apport report written because the error message indicates its a followup error from a previous failure.
                                                                                                          No apport report written because the error message indicates its a followup error from a previous failure.
                                                                             Errors were encountered while processing:
 linux-image-extra-4.4.0-89-generic
 linux-image-generic
 linux-generic
E: Sub-process /usr/bin/dpkg returned an error code (1)

Actually, it turned out the same errors appear when I am trying to install any softwares.

This is what I get and did:

Your problem is:
update-initramfs: Generating /boot/initrd.img-3.16.0-43-generic

gzip: stdout: No space left on device
E: mkinitramfs failure cpio 141 gzip 1
Solution:
apt-get autoremove

So I did sudo apt-get autoremove

and here are the outputs:

Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following packages will be REMOVED:
  linux-headers-4.4.0-72 linux-headers-4.4.0-72-generic linux-image-4.4.0-72-generic linux-image-extra-4.4.0-72-generic
0 upgraded, 0 newly installed, 4 to remove and 277 not upgraded.
3 not fully installed or removed.
After this operation, 297 MB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database ... 259942 files and directories currently installed.)
Removing linux-headers-4.4.0-72-generic (4.4.0-72.93) ...
Removing linux-headers-4.4.0-72 (4.4.0-72.93) ...
Removing linux-image-extra-4.4.0-72-generic (4.4.0-72.93) ...
run-parts: executing /etc/kernel/postinst.d/apt-auto-removal 4.4.0-72-generic /boot/vmlinuz-4.4.0-72-generic
run-parts: executing /etc/kernel/postinst.d/initramfs-tools 4.4.0-72-generic /boot/vmlinuz-4.4.0-72-generic
update-initramfs: Generating /boot/initrd.img-4.4.0-72-generic
run-parts: executing /etc/kernel/postinst.d/pm-utils 4.4.0-72-generic /boot/vmlinuz-4.4.0-72-generic
run-parts: executing /etc/kernel/postinst.d/unattended-upgrades 4.4.0-72-generic /boot/vmlinuz-4.4.0-72-generic
run-parts: executing /etc/kernel/postinst.d/update-notifier 4.4.0-72-generic /boot/vmlinuz-4.4.0-72-generic
run-parts: executing /etc/kernel/postinst.d/zz-update-grub 4.4.0-72-generic /boot/vmlinuz-4.4.0-72-generic
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-4.4.0-89-generic
Found initrd image: /boot/initrd.img-4.4.0-89-generic
Found linux image: /boot/vmlinuz-4.4.0-75-generic
Found initrd image: /boot/initrd.img-4.4.0-75-generic
Found linux image: /boot/vmlinuz-4.4.0-72-generic
Found initrd image: /boot/initrd.img-4.4.0-72-generic
Found memtest86+ image: /memtest86+.elf
Found memtest86+ image: /memtest86+.bin
Found Windows 7 (loader) on /dev/sda1
Found Windows 7 (loader) on /dev/sda2
done
Removing linux-image-4.4.0-72-generic (4.4.0-72.93) ...
Examining /etc/kernel/postrm.d .
run-parts: executing /etc/kernel/postrm.d/initramfs-tools 4.4.0-72-generic /boot/vmlinuz-4.4.0-72-generic
update-initramfs: Deleting /boot/initrd.img-4.4.0-72-generic
run-parts: executing /etc/kernel/postrm.d/zz-update-grub 4.4.0-72-generic /boot/vmlinuz-4.4.0-72-generic
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-4.4.0-89-generic
Found initrd image: /boot/initrd.img-4.4.0-89-generic
Found linux image: /boot/vmlinuz-4.4.0-75-generic
Found initrd image: /boot/initrd.img-4.4.0-75-generic
Found memtest86+ image: /memtest86+.elf
Found memtest86+ image: /memtest86+.bin
Found Windows 7 (loader) on /dev/sda1
Found Windows 7 (loader) on /dev/sda2
done
Setting up linux-image-extra-4.4.0-89-generic (4.4.0-89.112) ...
run-parts: executing /etc/kernel/postinst.d/apt-auto-removal 4.4.0-89-generic /boot/vmlinuz-4.4.0-89-generic
run-parts: executing /etc/kernel/postinst.d/initramfs-tools 4.4.0-89-generic /boot/vmlinuz-4.4.0-89-generic
update-initramfs: Generating /boot/initrd.img-4.4.0-89-generic
run-parts: executing /etc/kernel/postinst.d/pm-utils 4.4.0-89-generic /boot/vmlinuz-4.4.0-89-generic
run-parts: executing /etc/kernel/postinst.d/unattended-upgrades 4.4.0-89-generic /boot/vmlinuz-4.4.0-89-generic
run-parts: executing /etc/kernel/postinst.d/update-notifier 4.4.0-89-generic /boot/vmlinuz-4.4.0-89-generic
run-parts: executing /etc/kernel/postinst.d/zz-update-grub 4.4.0-89-generic /boot/vmlinuz-4.4.0-89-generic
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-4.4.0-89-generic
Found initrd image: /boot/initrd.img-4.4.0-89-generic
Found linux image: /boot/vmlinuz-4.4.0-75-generic
Found initrd image: /boot/initrd.img-4.4.0-75-generic
Found memtest86+ image: /memtest86+.elf
Found memtest86+ image: /memtest86+.bin
Found Windows 7 (loader) on /dev/sda1
Found Windows 7 (loader) on /dev/sda2
done
Setting up linux-image-generic (4.4.0.89.95) ...
Setting up linux-generic (4.4.0.89.95) ...



########################################################################
// Later on my computer at work, I was trying to install screen and I got:

Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following packages were automatically installed and are no longer required:
  linux-headers-4.4.0-70 linux-headers-4.4.0-70-generic linux-headers-4.4.0-72 linux-headers-4.4.0-72-generic linux-headers-4.4.0-75 linux-headers-4.4.0-75-generic
  linux-headers-4.4.0-78 linux-headers-4.4.0-78-generic linux-headers-4.4.0-79 linux-headers-4.4.0-79-generic linux-headers-4.4.0-81 linux-headers-4.4.0-81-generic
  linux-image-4.4.0-70-generic linux-image-4.4.0-72-generic linux-image-4.4.0-75-generic linux-image-4.4.0-78-generic linux-image-4.4.0-79-generic
  linux-image-4.4.0-81-generic linux-image-extra-4.4.0-70-generic linux-image-extra-4.4.0-72-generic linux-image-extra-4.4.0-75-generic linux-image-extra-4.4.0-78-generic
  linux-image-extra-4.4.0-79-generic linux-image-extra-4.4.0-81-generic
Use 'sudo apt autoremove' to remove them.
Suggested packages:
  iselect | screenie | byobu ncurses-term
The following NEW packages will be installed:
  screen
0 upgraded, 1 newly installed, 0 to remove and 264 not upgraded.
Need to get 560 kB of archives.
After this operation, 972 kB of additional disk space will be used.
Get:1 http://ca.archive.ubuntu.com/ubuntu xenial/main amd64 screen amd64 4.3.1-2build1 [560 kB]
Fetched 560 kB in 25s (22.3 kB/s)                                                                                                                                           
Selecting previously unselected package screen.
(Reading database ... 415154 files and directories currently installed.)
Preparing to unpack .../screen_4.3.1-2build1_amd64.deb ...
Unpacking screen (4.3.1-2build1) ...
Processing triggers for systemd (229-4ubuntu10) ...
Processing triggers for ureadahead (0.100.0-19) ...
ureadahead will be reprofiled on next reboot
Processing triggers for install-info (6.1.0.dfsg.1-5) ...
Processing triggers for man-db (2.7.5-1) ...
Setting up screen (4.3.1-2build1) ...
Processing triggers for systemd (229-4ubuntu10) ...
Processing triggers for ureadahead (0.100.0-19) ...

So I guess Ubuntu pushed some updates...

ref:
https://askubuntu.com/questions/517857/dpkg-error-processing-package-linux-image-generic-configure-dependency-pro