Category Archives: Troubleshoot

Olsson Block Low Temperature Troubleshooting

In my quest to have the best Ultimaker 2 possible, I have installed a Flex3Drive kit and Olsson Block kit.

Recently I have been having issues with inter-layer adhesion. I tried a speed test and would consistently fail them, either due to jamming or inter-layer splits… This is a story of how somebody more experienced in electrical and software engineering tackles a thermodynamics problem.

Bonus: this article contains a picture of my extra power 400W supply for the Ultimaker 2

Continue reading

Kinetis Microcontroller SRAM Region Hard Faults

I am doing a project that involves a K10DX128 microcontroller from Freescale, which is advertised to have 128 KB of flash memory and 16 KB of SRAM memory. It’s similar to the microcontroller used by the Teensy 3.0 platform. The project involves a lot of dynamically allocated memory because it deals with a lot of files inside a file system.

I ran into one of those “sometimes it happens, sometimes it doesn’t happen” bugs that causes a hard fault. Tracing the source of the hard fault lead to a few ordinary SRAM storage instructions, and apparently it happened half way through processing the list of files. This made me suspect that the memory was allocated incorrectly, and I checked all the things I should check(the address of the allocation, how much memory I should have, the status of my stack, the linker script, etc).
Continue reading

Upgrade a Passive HDMI Switch with 5V Power

I have many things connected to my single computer monitor via HDMI. I use a HDMI switch so I don’t have to unplug and replug cables all the time. But my cheap $6 HDMI switch is an unpowered passive switch, so it has problems working when the video source does not provide enough power to the switch.

For example, when my Mac Mini is plugged in, the 5V pin only supplies about 3 volts. Inside of the switch is a set of diodes and a AMS1117 voltage regulator that is supposed to output 3.3V using 5V, but instead it is only outputting about 2V. This made the LEDs in the switch flicker and blink (which seemed like a symptom of a bad power supply) and switch refused to function (no video output). My solution was to add a USB micro connector so I can add an external 5V power supply.

After adding the power supply, the switch is able to function properly with a steady supply of power.
Continue reading