This is not a difficult project, I already added SD/MMC card to my WRT54GL about 2,5 years ago. The difference is that there isn’t much guide about the hardware part (which GPIO pins to solder), and the software part (how to activate the drivers). So here is a short guide to anyone who needs it. Note that I already installed OpenWRT Kamikaze using the guide from: OpenWRT site.

This is what the front side of PCB looks like:

On the bottom right, you can connect a serial port (note: 3.3V, you will need MAX3232 or use a data cable from phone, don’t connect directly). Many guides are already available for connecting serial port (for example: here, here, here, and here), so I wont write about it. Just note that you will use the 3.3V and GND for the SD card mod.

This is what the PCB looks like from the back:

I found the GPIO pins from this posting by guidoa:


1: SES Button Blue led (Enable=ON)
2: WiFi led
3: SES Button Red led (Enable=ON)
4: SES Button (Pressed=01)
6: Reset Button (Pressed=01)
7: Status led (Enable=ON)

I have confirmed it using voltmeter and gpioctl command line tool. The SES button is the button on the right side of the unit. As far as I know, SES button, and the LEDS (red and blue) are not used by default, the Wifi LED is used to indicate Wifi ON/OFF. So we can use GPIO 1,3,4. We need another one: we can use GPIO 6 or 7. Since The status led is not used, I prefer GPIO 7. You can see the location of the GPIO pins that I used from the above picture.

Now, look at the SD Card Pinout (you can search it in Google, or just look here).
You need to connect SD Pin 4 to to 3.3V (see the serial port above), Pin 3 and 6 to GND. The rest is up to you (we will configure this later in software). This is what I use:

• Pin 2 (Data In/MOSI) to GPIO 4 (SES Button)
• Pin 7 (Data Out/MISO) to GPIO 7 (Status LED)
• Pin 5 in SD Card (CLK) to GPIO 1 (blue LED)
• Pin 1 in SD Card (Chip Select) to GPIO 3 (red LED)

After you solder them, you need to install these packages using opkg: kmod-mmc, kmod-mmc-over-gpio, kmod-mmc-spi, kmod-spi-bitbang, and kmod-spi-gpio. We need to edit /etc/init.d/mmc_over_gpio. The line that you are looking for is the add_device "default". There are some numbers in the following order DI, DO, CLK, CS and SPI_MODE. You need to fill in the GPIO that you use for each of that pins and just fill in 0 for SPI_MODE. In my case I edit the line to become: add_device "default" 4 7 1 3 0.

Now I can start the SD card using: /etc/init.d/mmc_over_gpio start. You can now mount the card. To remove the card, umount the card and /etc/init.d/mmc_over_gpio stop. The SD card speed is to slow, I will look on to this later, but for now the speed is enough for me.

This is my final result (I am really lousy at soldering):

Doesn’t look too bad from the outside for the SD Card:

But I made a stupid mistake for the RS232 port. I put the port on the wrong place, and I can not drill for the screw on the right side of the port. Fortunately this is not fatal, I just glued the port to the casing.

Update This is the dmesg log after /etc/init.d/mmc_over_gpio start

gpio-mmc: Failed to request mmc_spi module.
mmc_spi spi32765.0: SD/MMC host mmc0, no DMA, no WP, no poweroff
gpio-mmc: MMC-Card "default" attached to GPIO pins di=4, do=7, clk=1, cs=3
mmc_spi spi32765.0: can't change chip-select polarity
mmc0: new SD card on SPI
mmcblk0: mmc0:0000 SD512 495488KiB
 mmcblk0: p1

Update 9 April 2010 to make it clear, this is the picture of the back side of the pcb after soldering:

My wife was happy with her Asus EEE 701, but she would like something better with the same size. We sold the old Asus 701 to my brother, and she bought Asus EEE 900A. Compared to EE PC 701, the EEE PC 900A has a faster processor (Intel Atom 1.6 ghz vs the 900 Mhz EEE), more memory (1 gb vs 512 mb), bigger disk space (16 gb vs 4 gb), higher resolution (1024 x 600 vs 840×400), and better graphic processors (Intel GMA 950 vs Intel GMA 900). The only problem is the 16 GB SSD is much slower than the EEE 701 4 GB SSD. You can really feel it when running almost any applications, especially the firefox browser.

My wife uses Windows XP on the new Asus. After reading several blog posts and many forums, the conclusion is: to make everything faster, try to reduce the number of disk access. Here is how to reduce the disk access in Windows XP:

1. Buy more memory, we bought 2 GB memory  (quite cheap, around 690 baht/20 usd) to replace the 1 GB default
2. Allocate some of the memory (384 Mb for RAM disk). I set the environment variables TEMP and TMP to point to the RAM Disk. I also point firefox cache to the RAM disk.
3. Turn off page file
4. Disable indexing on all drives
5. Disable System restore
6. Don’t install firefox on the SSD. Firefox 3 will try to write its history every few seconds. I use Firefox portable on SD Card, and it is much faster now.

I found some other guides to speed up Windows on the 16 GB partition. I didn’t try all of the suggestions (too many steps), so I finally gave up because the speed improvement is not so much in my case. Finally I just moved the Windows back to the 4 GB SSD, and then reinstalling some seldom used software to the 16 GB partition.

When I bought a Torx T6 screw driver to replace MacBook Pro’s hard drive, I realized that the same screwdriver can be used to open P990i casing. So, I opened the casing, and I can pull out the old stylus. The stylus was stuck in a spring mechanism which I guess used to prevent the stylus from falling to easily.

You can look the disassembly pictures at
my photo album.

One thing that may not be clear from the instructions on the Internet is this: To open the part that covers the front camera: pull it upward (that is toward the upper side of the phone).

• Wikitravel info about Chiang Mai
• Thai Visa Many information, the forum is very useful
• Thai2English, if you are stuck trying to figure out a thai website, then this might help you. This is not a translation service, just word by word translation
• Thai text to speech If you want to know how to pronounce a word, you can use this online tool
• Many resources, including dictionary
• Chiang Mai News
• Thanni.com: Buy Electronic Stuff Onlne (I have never buy anything, but useful to know hardware price)
Chiang Mai Map. Complete map (powered by Google), searchable, they have photos of most places in Chiang Mai
• www.whatsonchiangmai.com

Don’t forget, Nokia Maps has a map of Chiang Mai for free. You can read more about it here

.

Instead, I will talk about information tecnology (IT) in Bali, specifically about Internet access and mobile stuff. Internet Access is quite easy to get, four stars and five stars hotels provides Internet access over WIFI, and sometimes I can find it at dining places. You can also access the Internet through GPRS or thorough 3G data connection with your cellphone. Starter pack for GSM is very cheap, but the internet access cost is quite expensive (25 rupiah/kb, or about 2.8 USD/megabyte, at current rate).

I haven’t been able to find a guide for Bali that can be put in my PDA or smartphone, so you will need to use online resources, or paper based information (from the Hotel, or from the airport). If you can speak english, you won’t need a translation program in your PDA, because most people can speak English.

May be you think I am a bit strange or too geeky: people come to Bali to enjoy the view and the culture, and not working with their computer. Well, I came to Bali to attend the Asia Open Source Software Symposium in Bali, to report the result of the Codefest that was held at Bandung, so going here is part of my work.

And now, as the AOSSS is over, I can extend my stay here, and enjoy my honeymoon.