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Jan Penninkhof Posts

Minimalist Cassandra VM using an OSv Unikernel

When I was living in Singapore I “accidentally” got involved in maintaining a community site for expats in Singapore. Till now, one in a while I’m still doing a bit of webmastering on the site as one of my side activities/hobbies. Use case As part of the activities on that site, there is a regular newsletter to all community members. Since the site was launched, approximately 350k members have signed up, but many of them have moved on to another country or changed their email address. At the same time, despite various anti-spam mechanisms the member-database is also getting polluted…

Why you should use MQTT in IoT projects and why SAP should support it

While designing an IoT device, there are multiple options to connect them. Once of the considerations should be the protocol being used to chat to other devices or to a server. Previously, I would have easily chosen to make the interface REST based and have done so with Jeenode project a few years ago. But REST is not ideal as it is designed around a simple request/response model. So you ask “did my account balance change” and the response is returned “no it did not”. So you check again a few minutes later, and get the same response. Sound like…

How to program an ESP8266

It is not difficult to program an ESP8266, especially if you already have some experience with embedded devices such as the Arduino. An ESP8266 actually works quite similar to an Arduino. Although you can barely speak about an operating system, your program is embedded in firmware and using some hooks, it is possible to run custom code. In most Arduino sketches the most important hooks are setup() and loop(). Setup is called when the Arduino is booted up (or reset), while the loop routine runs over and over again forever. The ESP8266 works in a more or less similar way,…

Setting up the ESP8266 Open SDK

It seems that a large part of the ESP8266 community has moved to the esp-open-sdk toolchain. And for a reason: the esp-open-sdk is much easier to install and update. Besides that, the esp-open-sdk replaes many of the proprietary libraries with open source versions.

Just as an exercise, I decided to give this toolchain a try as well, starting with a bare Ubuntu 14.04 (server) installation as its foundation again. It was my goal to make the same blinky run, but this time through the use of the esp-open-sdk toolchain.

SAP UX Tweetchat with Sam Yen (February 26th)

Last Tuesday, I had the opportunity to host/moderate a tweetchat with Sam Yen, who is chief design officer for SAP. I knew Sam Yen from a Teched Live interview that I did with him before, and knew about his passions with regards to user experience and design thinking. Sam has been leading the shift from feature thinking to design- and user-experience thinking at SAP. And that is important, as end-users expect much more from their users-experience. While doing their work at the office, today’s users expect the consumer-like experience that they see from their smart devices and consumer applications. Not only is…

Getting started with the ESP8266

I’ve always loved to play with Arduino’s, but also thought it was underequiped. There must be at least something that connects it to a network and should have at least a radio on board. Because of that I got really excited about Jeenodes, which had a RF12B radio on board (really good for low-energy, battery operated stuff), and was a couple of factors smaller than an Arduino at the same time. But that was back-then. Theres a new kid on the block that offers a very nice set of features, and doesn’t only just have a blip-radio built-in, but has…

SAP TechEd && d-Code 2014, Geeks Can Dance Band

After the success of 2013’s SAP Jam Band, Mark Finnern also got the band back together at 2014’s TechEd && d-Code, rebranded as the “Geeks Can Dance Band”. And similar to the year before, we once again could count on an awesome audience! 🙂This is a picture of the audience from where I was sitting:   Related: Mark’s announcement

SAP Hana Café NL – second edition

The second edition is out now!!! Please find this episode’s topic below: CodeJam SAP River Recap of the event at March 7, 2014 Recorded in English with Inbal Zilberman, Yoram Hod, Fred Verheul, Jan-Willem Kaagman, Jan Penninkhof, Roel van den Berge and Twan van den Broek What is SAP River? What to do as ABAP developer? VNSG focus groep SAP Custom Development Opgenomen in Nederlands met Jan-Willem Kaagman, Fred Verheul, Rob van der Marck, Jan Penninkhof, Roel van den Berge en Twan van den Broek Waarom een nieuwe focus groep Wat gaat de focus groep doen Agenda Kickoff meeting

HANA Café NL – The inflection point

SAP HANA Cafe Netherlands – a series of podcasts about all the fun things in our life as SAP developers. Roel van den Berge, Jan Penninkhof and Twan van den Broek will start and invite other friends of the Dutch SAP Mafia to join in the coming episodes. We want to address: SAP development (ABAP, HANA, SAP River) User Experience SAP’s platform Integration (Process Orchestration) Mobile Fun SAP stuff 😉 One downside for my international readers – it will be in Dutch… Last week we visited SAP d-code in Walldorf and decided to do a wrap up. Season 1, Episode 1…

Reasons why SAP should open-source SAPUI5

Everyone that has been at a recent SAP Teched, or has come in contact with Fiori in another way, knows that SAP is dead serious about UI5, as the UI development toolkit going forward. At SAP Teched 2013, SAP announced that Fiori Wave 2 gets +150 new apps all based on UI5. Fiori will become the new user experience for a consistent experience across all SAP solutions More partners and individual developers inside the SAP ecosystem are also trying to adopt UI5, to keep up with the train that SAP has brought to speed. However, because of licensing issues, many…