2013. augusztus 15., csütörtök

Work

As of today I'm working at a new place.
Here:


The things what the R&D team is doing in the company is a little bit futuristic to me but my duty is only the support of the infrastructure: Windows, Exchange, SQL, CRM, some Linux, etc.


2013. augusztus 14., szerda

Installing Ubuntu on BeagleBone Black 2.

Last time here I wrote about my adventure with the BBB and Ubuntu.
Now I have a task to create a kiosk like something from the BBB. When I tried to install the desktop environment on the BBB realized, that it won't fit into the 2GB integrated MMC. To go further - If I install the ubuntu image to an 8 gig SD it still create a 2 gig ext4 filesystem. When I tried to expand it I get some strange error. Finally found the solution:
  1. Put the SD card into an USB reader and connect it to the BBB
  2. Boot the system from the MMC
  3. Install the ubuntu image to the SD card as mentioned in the previous article
  4. delete the ext4 partition (namely: /dev/sda2) with the cfdisk and recreate it to fill the whole free space on the SD card (in my case it will be a partition little bit smaller than 8GB)
  5. Repair the partition:  e2fsck -f /dev/sda2
  6. Expand the partition: resize2fs /dev/sda2
  7. Shutdown the system
  8. When it finished you can put the SD card into the holder on the BBB, boot to ubuntu and do whatever you want
After that I installed the xubuntu-desktop environment but realized that it extremely slow and even hangs after a few mouse clicks.
Today in the morning I reinstalled the whole thing with lubuntu. I had no time to wait the completion of the process. I'll see afternoon if it works correctly or not.

2013. augusztus 13., kedd

Sample ordering - Next Round

As a month ago I ordered some engineering samples. This time not from TI but from Maxim Integrated. Today arrived kind letter asking me to fill and send back a Statement of Assurance letter for the US Export Control.
This time I'm not as lazy as last time. I just filled and sent back the form almost instantly.
We will see what happening.

2013. augusztus 8., csütörtök

Double Multiplex 3.

The PCB fully finished now and I created a test code for MSP430 (it is still bumpy a little bit and ~600Byte). It working quite well but the brightness is not to high. Actually in theory it has 12mA current per segment what I don't want to increase for testing (In theory I can increase it ot 20-25mA. The LEDs are capable to handle 100mA with 1/10 fill factor but the MCU don't). So I've 33ohms current limiting resistors what finally can be decreased to 22ohms: (3V - 2,2V) / (2 * 22) = 18mA.