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Showing posts from August, 2006

Moving code from ESP8266 to ESP32

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A while ago I made a mashup of Dan Royer's code CNC 2 Axis Demo with my own code for trapezoidal motion stepper and servo control for ESP8266.

I assumed porting the code to the ESP32 would be trivial, and that was true for the most part: changes like library name being Wifi.h instead of Wifi8266.h were not a problem. UDP now does not like multicharacter writes but you can use print instead. So far so good.

However, when it came to the interrupt code I was stuck with the stepper interrupt causing an exception sometimes. And to make things weirder, the servo interrupt worked flawlessly (both of them had the IRAM_ATTR directive if you ask me).

Going little by little, I could narrow down the culprit to a floating point operation during the interrupt, that would cause problems sometimes but not always. Browsing around I found this post. Where the solution was simple: do not use floats within the interrupt routines but doubles. The reason was the float calculation would be performed by…

Space-age sunglasses

I was having a beer with a friend in a small cafe in Peñíscola. Later, when we headed to the beach my friend missed his sunglasses. He was recently shooting a movie in the Moroccan desert. When we returned to the cafe looking for the sunglasses we were told nothing was left on our table. However, after insisting on our point the cafe owner "discovered" the sunglasses in their box. Curious.

I was not familiar with that brand and my american friend told me it's Revo, a high-tech brand of sunglasses that claims to offer the best bandpass filter using space-age technology. I cannot tell you first hand, but on paper they look good if you have two hunderd dollars to spare. They are only available in USA though.

Toshiba Qosmio F30 oddities

The Qosmio line from Toshiba adds a new capability to their laptop line: It's a DVR and DVD player using some BIOS software. The result is that you don't need to boot any OS (i.e. Windows Media Center) to use these features. It also means that even if your system is destroyed by a virust these features will still work. On top of this, Toshiba ships the system with a remote control that will make your experience even more comfortable and the Harman/Kardon loudspeakers deliver a good audio experience too (with richer bass sound than most other laptops).

But there are several catches that Toshiba let slip under the carpet. My first surprise was that inside the package they include a USB infrared receiver. My first thought that it could be there just in case you do not have a good angle when using the built-in receiver. I was wrong. I latter learned that Media Center Software is not compatible with the laptop's built-in infrared receiver so the USB one is required to use the r…

Weird Wireless

I'm visiting a friend who has a new house and a new wireless setup from Telefónica. He needed some help from his company IT department to get the thing working. On arrival he tells me that he can use the wifi connection and it works, but at the same time the computer says it is not connected.

I suspected that odd behaviuor could be due to the common WinXP/manufacturer driver schizophrenia where both the system and the wifi card manufacturer's software are trying to manage the card settings. I tried to disable the WinXP handling of the card but then I was getting disconnected. So I tried the wifi card's software: Hmmm, cool! Network scanning shows a beautiful sonar-like display where you can the different networks on your neighbourhood, names, MAC addresses, channels and ... surprise: There are two different AP using the same ESSID nearby on different channels. This is probably because a neighbour has a similar setup as my friend's.

Ok, time to change the ESSID to somethi…

Getting a ticket to Oulu

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I have to visit Raahe (near Oulu, Finland) in September and the EU is quite stingy about ticket cost (unless you are a politician which I am not). Our staff wanted to get it done for not more than 650 Euros. Most airlines either do not fly to that destination or charge you more than 1000 Euros. Time to put some of my vacation time to the task of saving some of that taxpayers' hard-earned money.

The old fashion way of using a brick and mortar travel agency seemed to be a no go, as I am still waiting for a quote from them. Expedia or Travelocity had served me well in the past but it is unclear if you can get a ticket from them if you are based in Spain.

A local e-company, rumbo.es provided a very nice price of 476 EUR, but when I tried to complete the check-out it gave me an error. It was also unclear whether I would need to go to baggage claim when changing airline or not. It was time to give them a call (or more).

First call: All our representatives are busy, line hung-up. (Nice cust…

Carry-on e-gear

I've just realized how many different devices my family is carrying around when traveling. I mean computer-based devices. I can count two laptops, three cellphones, five MP3 players, one DivX hard drive, one mobile DivX player with a small screen, a nice unit that doubles as a flash-based MP3 player and self-powered loudspeakers, a Palm PDA, a fantastic CASIO dictionary plus translator and a Canon digital camera.

It is an amazing number of devices that suggests me that, at least for us, we are really far away from those devices that do almost everything. We are more the kind of customer that prefer one device that performs one task well. But I guess that other customers will enjoy multifunction devices. Just a question of user preferences.

Xtreme summer sports: Internet access in rural areas of Spain

It should not be that difficult. After all, last year I was attending a free Internet access (wifi) on a public libary in the north west of Spain (Galicia). But this year's experience proved quite tough and challenging.
To make a long story short I will tell you the local hotspot was not properly configured to accept user's laptops. So until I was able to let that message reach the network management people the problem prevented me to access the Internet. The problem, as with cellphone operators, is that their CRM is designed to prevent user's complaints to get to the right technicians. So it took me some courage and time till I got things sorted out.
Right now I'm sitting on the street with my laptop writing this message. The speed is so low that I am not sure I will finish the post before running out of battery :-)