Showing posts from June, 2010

Moving code from ESP8266 to ESP32

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…

Unexpected treat

Now that the classes are over and I'm thinking about a summer trip I've got myself a new camera. Two years ago I was impressed with Panasonic DMC-LX3 camera but I did not buy it as I've just bought a DSLR by then.

Last night I was checking prices on eBay and I saw a good deal for a Canon S90. I checked its features and it turned to be Canon's answer to Panasonic's LX3. It also has a nice F2.0 lens with more zoom than LX3 (28-105mm), a 10 Mpixel sensor and a nice 3" display. It has plenty of manual control and a myriad of shooting modes too. And it is compact, a bit more compact than LX3. I was not planning on buying it but apparently nobody else was interested on bidding and below $300 it was a steal.

My first experiences with the camera are good. Not really sure about the best way of holding it as it is quite small. The worst part is the wrist strap that does not seem to fit nicely.
She will explain all the basics better than me.