mercoledì 24 ottobre 2012

Menuet OS power in my hands!!


Five minutes trying Menuet OS 0.98.84 64-bit (released yesterday) in VirtualBox 4.1.12 under Ubuntu 12.04:

- duh, it just works...!

- entire distribution fits in a single diskette image (1.44Mb; you can easily build the CD image... 1.5Mb: yes, 1.5 megabytes)

- pre-emptive multitasking with 1 KHz scheduler, multithreading, SMP up to 8 cpus, hard real-time data fetch support, etc: oops, while in Virtualbox this means it sucks all available CPU power; I guess it is due to 1000Hz scheduling (host machine was set with a 70% cap, resulting in more than 50-60% cpu usage while running a few demos)

- responsive GUI working on VESA standards, using transparencies and skinnable windows and drag'n'drop; mouse did not require particular Virtualbox configuration. It was a bit eerie navigating windows with that two non-aliased fixed-size fixed-width fonts. Has a starting "Menuet" menu in the bottom-left side of the screen; the always visible bottom area contains running program names. A weird thing was the need to click the "Menuet" button to wipe out the opened menus/submenus.

- editor and assembler for applications (yes, you will write apps using assembly language; the operating system itself is written in x86 assembler, both 32 and 64-bit; the assembler of choice is FASM);

- USB support for a few peripherals (including USB 2.0 storage, webcam, printer, TV/radio, and USB 1.1 keyboard and mouse); USB boot supported (I did not yet test it)

- TCP/IP stack with utilities (HTTP browser and server, FTP client and server, etc; sadly, it seems to lack a PING utility); networking addresses can be configured in the first phase of the boot (oops: only fixed IP addresses, no DHCP seen yet)

- system configuration at boot time in a commented text-file full of hex numbers (nerdy style)

More news coming soon...!

domenica 21 ottobre 2012

Nokia N900: broken USB, fixing charging

I had to abandon my first Nokia N900 because of broken USB port. The microUSB receptacle of the N900 is directly soldered on its mainboard (yes, the most stressed part of the phone without any safety: brain-damaged engineering is not an Apple exclusive).

When it broke, I bought a second N900, saving the first one for backup purposes. And after one year of careful usage, on a Friday late evening it suffered the same fate, meaning that:
I won't ever buy Nokia products again.

Sala operatoria: pronti per l'intervento sul Nokia N900
MicroUSB port is required both for data connection and for battery-charging. Without the microUSB port, you need to power off the phone, take out the battery and charge it on some external charger, which is quite annoying.

After a bit of googling I decided to put a header in place of the microUSB-receptacle but it was even harder than imagined. The five "pins" of the receptacle are some tiny 0.5mm-spaced drops. I eventually was able to solder D+ and D- cables (photo below), which are needed to use "tethering", that is: charging the phone while you use it as a modem. But -sigh!- a few minutes later I crashed them without hope to restore (they were not meant to resolder). This means I have to forget about tethering.

La monetina da 0,10€ serve per far capire quanto erano "grandi" e "vicine" le saldature da fare
Then I decided to short them; shorting D+ and D- (or, at least, 220 Ohm resistance) is required by the N900 to accept any 5V source to charge the battery. Fortunately, GND and +5V are replicated on the "test pads"; GND is also the center pin of the battery connector.

Applying +5V to the 5V/GND pads will regularly charge the BL-5J battery because D+ and D- are always shorted.

Opening the N900 was quite easy: four small screws for the screen and two small Torx for the keyboard and keyboard cover. More on that on talk.maemo.org forum.

Recuperati 5V e GND e "shortati" D+ e D-
I am now able to charge the N900 without having to power off / extract battery. After a bit of dremeling, I steadily placed the ugly 4-pin female header (chosen because "safe for my pockets); it does not perfectly fit, and my N900 does not "close" well, but at least I don't have to switch to another phone (moving calendars, addressbook, music, videos, etc and learning apps, configurations and so on).

I also switched screen and keyboard (both a bit scratched) with the ones from my first N900, so that my current unit feels somewhat rejuvenated...

L'orrendo header femmina serve a non far pasticci quando l'N900 è in tasca

giovedì 18 ottobre 2012

Paesaggi urbani

venerdì 12 ottobre 2012

Manicaretti vari - #instaGnam -

...Tra cui Giovanni Rana, al quale bisognerebbe erigere un monumento!

giovedì 11 ottobre 2012

Slurp! Chomp! #instaGNAM!

Note:

foto 1: l'intingolo

foto 2: ravioloni ricotta e limone

martedì 9 ottobre 2012

lunedì 8 ottobre 2012

martedì 2 ottobre 2012

Pubblicità dei videofonini nel 1910


1910 - “Telefono privato e televisore senza fili.

Ognuno adesso ha un proprio apparecchio ricetrasmittente e può conversare, su una determinata lunghezza d’onda, con amici e familiari. Ma anche la tecnica televisiva si è talmente evoluta, che nel contempo si possono guardare i propri amici in faccia. Gli apparecchi ricetrasmittenti non sono più legati a un posto, ma vengono portati sempre in giro in una cesta delle dimensioni di un apparecchio fotografico.”

Come dice la nonna: "Cu stì telefonì, quanti chiacchiere à bacànte!"

(fonte: Kelebek)