Downloading older versions of macOS

Apple digitally signs the installers used by its software updates. The certificates Apple used to sign these installers have expiration dates which is causing old installers are no longer working. But there is a trick to still download old installers. Apple has re-signed and re-released older installers, giving them a new expiration date of 14 … [Read more…]

Simpler Mini Booster für die Modelleisenbahn mit MAX14870

Für Modelleisenbahn gibt es von den verschiedensten Herstellern Booster, um digitale Protokolle auf die Schiene zu bringen. Ich möchte in diesen Beitrag darauf eingehen, wie man sich möglichst klein und günstig einen eigenen Booster aufbauen kann, der natürlich vom Funktionsumfang sich stark zu komplexen Boostern unterscheidet. Hierzu ist es wichtig zu wissen, dass es verschiedenste … [Read more…]

Apollo3Blue I2S via hardware pattern generator

In my last article I had described the capabilities of Apollo3Blue generating pattern in hardware: In this article I will go a step deeper inside implementing a full protocol for driving audio: I2S. In general I2S is used to transfer left and right channel data in a 16-bit PCM format for each channel with a … [Read more…]

e-Peas AEM10941 Energy-Harvesting PMIC with Ambiq Micro AM1805AQ PMIC-RTC

  Ultra-Low-Power energy harvesting applications often requires some “black-boxes” for finding the maximum power point between current and voltage consumption to harvest energy, a DC-DC converter to charge a storage element, some LDO for providing the target MCUs operation voltage and some kind of timer to wakeup the application periodically or wakeup by request via … [Read more…]

Apollo2’s hidden USB

Apollo2’s hidden USB is not a hidden hardware feature, but software bit-banging using Apollo2s flexible GPIOs including the capability to drive 1.5k pullup resistors on special pins used with I2C.The following picture shows the connection between MCU and USB port: The solution supports low-speed USB for realizing HID USB transfers for example. One idea is … [Read more…]


Apollo3Blue is now available in Europe via the webshop of Fujitsu Electronics Europe GmbH: The best way to start with Apollo3Blue is to use the evaluation board For later on prototypes Apollo3Blue is available in BGA (AMA3B1KK-KBR) or as CSP (AMA3B1KK-KCR) Datasheets and latest software is available at the Ambiq Micro … [Read more…]

ClickBeetle Model-Train Controller

Looking back to the magic N-track train I was searching for something bigger but using the same firmware with advanced features. I decided to keep the ClickBeetle standard to add more boards offering to possibility to build a flexible HMI.      The base board called HmiBeetle is capable to add up to 5 ClickBeetle boards … [Read more…]