So what do you do with a Holux GPSlim240 or a Holux M241 GPS Logger? Well, I bought them before I had a reason. Yes, thats exactly like me. First I bought the world’s smallest bluetooth receiver Holux GPSlim240. It reached without trouble in 7 days. I worked with it for a about 2 weeks. Used mGMaps on my K790i. Later also installed Nav4All. That was what I thought to be fully loaded until my bro vivek told about the M241.

The Holux M241 GPS Logger is high end system for those who know how to use it. For silly people it simply comes with a LCD to let you see the latitude, longitude, altitude, speed, time and total distance traveled. So yes, you don’t need a bluetooth receiver at all times. For utter crazy dude like me, it can log. That alone is the super duper system to be used in so many ways. Welcome to openstreetmaps project. The ride has just started boys!

OpenStreetMaps is a great project for its letting anybody map their locality. In the case of INDIA, Google or Yahoo both have very bad quality satellite images and that too more than 2 years old. The locality where I live is mostly empty lands on google earth while in reality there are like 5000 apartments around. I started OSM after 3 weeks back when I had bought my first GPS receiver, Holux GPSlim240. It worked great (almost). I installed loads of softwares on my K790i and started playing with it. First I installed mGMaps. Its a mapping tool to render maps or terrain from various sources. When I first found out about mgmaps it could even render GMap. Now it can render everything but gmap. Haha. The interesting thing is that it can even render OpenStreetMaps along with wikimapia. mgmaps is great software and u can actually use it to travel to ur destination as it can hook to a bluetooth GPS and show position in realtime! (DO NOT USE IT WHILE DRIVING!). You can add bookmarks and zoom or pan around the map just like it were a web browser. Finally, mgmaps also supports realtime upload of the position. Therefore, if my profile can be accessed, you could even track me in realtime. My phone with the GPRS will keep uploading the coordinates to the mgmaps server. mgmaps also supports a great new function of friends. It will getting coordinates of all of its friends and display them on my phone’s screen. Same way will display my position on my friend’s mobile screen. The next amazing software for realtime GPS navigation is Nav4All. Nav4All is also a J2ME application just like mgmaps and works perfect even for my indian roads. Certainly it does not have all the roads that we know but it is growing. I don’t think its using OSM or any known data sources. It comes with a big bunch of audio languages and has a clever UI. Supports Night mode display as well has Economy intelligence over it for saving the mobile battery. Nav4all also supports uploading the points to the server but I have not tested its realtime engine. Then I tried to use GPSed. Its a data logger software which will write the info into a file on ur phone after it gets points from the bluetooth GPS device. The problem with GPSed is that on my phone it is very CPU hungry. Most often it responds very slowly and secondly on my phone it rarely succeeds in writing data to the file. At the end of the session when I want to save all logs it has failed everytime. Im not sure that this is cause of the security settings or not but I could not use GPSed very nicely. Besides that, it does have fearures to upload the log to its server. That is when I needed the Holux m241 Data Logger, the thing needed for GPS Tracing.

Openstreetmaps has been contructed in many ways. One of the very common methods for mapping has been GPS tracing. Since no overlay map can show a locality better than you being their yourself, collecting the GPS traces will allow you to later map your path even without the need of any satellite imagery. For my case its the only solution since my locality is no where seen in the satellite maps. I collected lots of traces from the m241 and later converted them to GPX format. OSM accepts GPS traces ibn GPX format. The Holux download utility that comes with the driver CD allows changing the log type from TRL into KML, NMEA and GPX formats. That is what I upload to see my trace on the mapping toll (either Potlatch or JOSM).

I will continue this blog for next few days with lots and lots of links cause I did not get all those in one location.

I’m badly looking for a method so I can extend or create my own firmware for the camera of my choice. All camera have their own RTOS and hardware. Therefore I should not expect same SDK for many camera companies. But I can expect same SDK for many models since same companies very much use same environment. More critical than anything is that the manufacturers hate to offer any such feature. I have a Casio EXILIM EX-P505. The camera is very good. I can’t say that more. Its so good that I want to extend it. I use it for Time lapse imaging. If I could automate the clicks for every 60 seconds or so, it would be very easy to do such photography. Yes, web cams can help me on that but web cams are very low of resolutions. Added they will need a whole computer along therefore no portable at all. I have been googling a lot for my cam model and few others but not found any crack to the problem. Some have parsed the firware update and split the files into ROM and JPG and music etc. ROM is assembly compiled written most likely in C. Reading the ROM of my casio i find paths as A:. Means the RTOS is very much like DOS STDLIB. That is good news but again getting a compiler or decrypting the compiled code is going to be hard. Then there are other problems as missign documents and interrupts. What button does what. How to trap events. All will have to be reverse engineered. Pain Big Time. Its sure possible for Pro. And thats not me! So I wrote this blog so anybody of similar interests or with leads on thsi topic can have some thoughts. I will write more on this topic soon.

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Chapter 4

By the time i came to this spot it was Janurary 2006. Just the month before I had prepared a the circuit for LCD and AVR. This till date was the most complicated component. I did not know any basics about using LCD which hurt the most. The initial circuit was just made as shown. (more…)

I needed to write a entire account of the last 6 months that I started into ATmega8535. Then I was aware of nothing in electronics except basics upto transistors. Comparing that today, the things I learned is avery long list. these 6 months therefore I term as my first semester. Just for you all readers knowledge, Im not at all from science background. So lets get started.

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simpe reading and writing bytes between hyper terminal was fun. baud rate was 2400bps though and when i typed too fast the uart_getchar() would return a 255. i don’t know why. otherwise, in synchronized manner, this will work very neatly. the interrupt mode will be attempted when I get back home.

After the wiring completed, i checked the stage 1 test, that is, to short rx and tx pins coming from DB9. hyperterminal kissed me. Stage 2 test was to short the output ports of max232 after i connect the DB9 wire on it and power it up. The terminal loves me! It is 20 minutes to 4 am, i gotta get her to bed so working on it!

The same board with running 16×2 LCD was used to try the ADC circuit. ADC actually turned out to be far too easy than i had thought. I could not find a good device to get Analog from (like LDR or NTC) so to start i put the 10K preset i had bought for LCD on the ADC Pin 0 - PORTA0. AREF and AVCC are both set to +5v and AGND to GND. Then the program did the rest. peanuts!

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614, lajpat rai market (mehta bros) gave me a L serios of 8535 and I had to spend 2 weekends to realize it runs only on +2.5 volts while my programer was trying it with 5. the programming was tweaked to send +2.1v and then both avrdude and avr-prog were happy. It was real hard work to just let the programing even tell me that they found the chip. the limitation only is that atmega8535L can only run on a max 8mz crystal unlike 16mhz max for a general ATmega8535.

to assemble a entire circuit using a ZIF socket and LCD for 8535 takes under 12 hours. which I call as expert. :P. the assemble is sets RS/RW/E pins on first three pins of Port C while data on port B. The plan was to free my ADC on port A and and UART pins on port D which left me with port B and port C. port C still has space for clock crystal. the possible bad news is by MISO and MOSI are used by the port B so im not use my version ISP (in circuit programmer) would run on the same circuit or i would need swicthing. anyway the curcuit has been planned to use LPT for programming while rs232 for interfacing so both activities can theoritically happen wihout me changing plus. LPT is anyway missing from new boards. mine is p2gz845 which does have it.

Bringing my programs to life outside the stupid “personal computer” feels really something. The task that started at mid September, 2005 is reaching new heights. I having no physics or science background and being hopelessly bad in mathematics, i still survive the challenge. (more…)