Turtle Hat

I learned to knit when I was deathly ill on New Year's.

After the perfunctory "hello world" of knitting, a scarf, I tried to do something a little more interesting.

I came across some "hairy" yarn in a mossy green color. I decided to make a "turtle shell" hat.

This was my first real project. I didn't have a pattern; so I made it up on the fly. The first attempt was HUGE. Yeah, round 2.

I shrunk it and did a 2x2 rib. I used 2 continuous strings (green and brown). When I was done, it was gorgeous. Super cute, perfect, and.... SMALL.

It was so tightly knit from carrying the 2 lines the whole time. I gave it to a friend for her doll.

I was so frustrated, that I promised to never do it again. Instead I did a simple grey hat, fast, easy and pretty.

Then I got the itch to try the turtle hat again. This time I ran 12 lines! One for each color and patch. It was a difficult task to keep everything straight, but it worked. This time it was JUST RIGHT.

I gave it to my niece(nicknamed "Princess Turtle"). I would like to thank her for being my model.

Spy Trakr: Headphone Jack

The first hack everyone does to the Spy Trakr is to install a headphone jack. I jumped on the band wagon. My biggest issue was the mic-speaker feedback when I had the Spy Trakr next to the remote; LOUD!

So I opted for headphone jack AND a volume knob.

I carved out a slot in the right grip with a soldering iron (it is a sin, I know) for the jack (ebay 5-pin) and a small wheel potentiometer (Radio Shack 271-001). This 5-pin jacks automatically switch from speaker to headphone when you plug it in.

This is a crude wiring diagram. It is sad how long it took me to figure it out.

This is a shot of the holes and where the stuff fits in the remote.

The components assembled and awaiting final gluing.

The final installed setup.

The speaker shuts off when the headphones are installed.

Speaker: the wheel controls the speaker from NORMAL to mute. Not a lot of fine control.

Headphones: the wheel controls the headphones from REALLY LOUD to NORMAL.

Overall, I am happy with the results.

Spy Trakr: Motors

There are many complaints about the Spy Trakr motor; all of them say it's too weak.

I opened it up to see what we were dealing with.

Four gears in the train from the motor to the wheel

10:28

10:38

10:38

overall 1:40.4

Should be beefy enough, but the motor spins so slowly; the wheel does about 100 RPM.

Three wires to the motor: black, red, orange (the other wheel is green, blue, yellow)

This is a simple brushed DC motor. Orange/black power the motor and red is a ground to motor chassis.

The motor itself is a little larger than the typical guys I see at the hobby shop.

I will revisit this later to get a better idea of the motor, and how to improve the situation.

Spy Trakr: Wide Angle Lens (more)

A little bit more about the lenses and installation.

This is the 1.8mm lens installed on the board.

I had to make a custom lens holder and I made it a little loose. The lens would shift when I installed it in the TRAKR. So I manually focused it and dribbled Elmers glue into the threads overnight. Now it is sturdy enough to install in the 'bot.

These are 3 of the 4lenses I used (excluding the one I installed).

The TRAKR lens is on the right. It has a 9mmx0.5 thread on the lens. This diameter is less common, but not too bad. The screw holes on the lens mount (and the TRAKR CMOS) are 18mm apart. This lens has an IR filter built in. This lets 850nm pass and blocks the other IR frequencies.

The other two lens are from the Surveyor SRV-1 (basic on left, wide angle in the middle). These are both 12mmx0.5 thread lenses. Much more common size. The included lens mount is on the center lens. The screw holes on the lens mount are 22mm too big for the TRAKR.

So I built my own lens holder: 12mmx0.5 thread with a narrow 18mm base. Not hard, but I was sloppy (thus the glue)

Spy Trakr: Wide Angle Lens

I recently purchased a Spy Gear Spy Trakr. $80 R/C Tank with video camera that displays on the remote. It's claim to fame is that it runs Linux and is user programmable. Hackaday.com did a few good write-ups on it //hackaday.com/2010/08/27/spy-video-trakr-first-impressions/

Unfortunately, Spy Gear has stopped supporting it and taking the source code with it. Darn.

In the meantime, it is still a fun little toy. I drove it around the apartment, tough to navigate on the small screen. Just for giggles, I thought I would swap out the lens with a wide angle lens. I had 3 other lenses from work: 3.6mm, 2.2mm, and 1.8mm. (The Spy Trakr lens looks to be 3.6mm).

These lenses are 12mmx0.5 thread, very common; the Spy Trakr lens is 9mmx0.5 thread, less common.

This is an image with the default lens

This is an image with the 1.8mm lens

A top view of the kitchen, er... test arena.

The green line is 1.8mm and red is the 3.6mm.

The wider view and increased "peripheral vision" make the Spy Trakr an order of magnitude easier to drive.

A couple of notes about the 1.8 mm lens. It was labeled as 180-degree field of view. Clearly not 180 degrees. The fine print is that on a 1/3" imager it yields a full 180-degrees, but on the Spy Trakr 1/4" imager, we get 90-degrees. Again, still better than the 45-degree Spy Trakr lens.

A problem though, the wider lens needs A LOT more light. Thus my images are bad outside of natural sunlight. D'oh. External LEDs will fix that.

68HC11 Bootstrap mode

In 1999, I received a Super T-Comp; a 68HC11 based microcontroller board that is similar to the Handyboard.

While working with it I released the sacred smoke. I blew out 3 chips.

I repaired the damage, but I couldn't get it to work right again. So it sat in my toybox waiting for me to try again.

In 2010, I am taking a class in embedded systems; so it is time to try again.

Inspecting the board again, I found a bad chip that I missed; a NAND gate driving the external RAM. I will fix that this week.

Regardless I should be able to talk to T-Comp in Bootstrap mode. PCBug11 is the original tool for talking to 68HC11. It doesn't run on modern (fast) computers.

So I tried TeraTerm terminal software. Finally did established communication this morning.

68HC11 has 4 modes:

Single Chip: no external RAM

Expanded: external RAM

Bootstrap: single chip, using bootstrap loader in ROM

Test: Uh? don't know

Bootstrap Mode

Hold ModA and ModB low

Toggle Reset

Release ModA and ModB

within a second

send a byte over SCI (serial port) at 1200 Baud, No parity, 8 bits, 1 stop bit.

It is now ready to accept a 256 byte program. 68HC11 will echo bytes. Once it recieves 256 bytes, the program counter resets to $0000 and starts to run the loaded program. In theory.

Hacking the PSP

Everyone has hacked the PSP to put non-Sony firmware on.

You can still run your games, AND install homebrew stuff.

This was the original goal when I bought my PSP. I got distracted by actually playing games.

I finally got around to doing it.

I have the GOW edition PSP slim, it had Sony firmware V3.94 installed.

I sort of followed the instructions that I found here

http://forums.pspslimhacks.com/tutorials/5-guide-psp-custom-firmware-reference-guide-minor-update.html

Things you need:

Pandora Battery - modified battery to allow access to the PSP bootstrap mode,

I borrowed one

Sony memory stick - 1Gb stick works fine

PSP Grader v0.008 - installs firmware, I got it here

http://pspslimhacks.com/psp-grader-v008/

modified PSP firmware - overwrites the Sony firmware, I got it here

http://www.psp-hacks.com/file/1568

Connect the PSP to your PC; start USB mode.

Copy the Sony memory stick to PC

Format the Sony memory stick

Start PSP Grader

Locate the eboot.pbp in the PSP_500_FW.zip

Download file to stick

Disconnect and power off the PSP

Remove battery

Insert memory stick (if you haven't)

Hold down the L button

Insert the Pandora Battery (often PSP auto-starts) and start PSP

Back up NAND

Restart PSP

Install 5.00 M33 (or similar)

Done.

I have spent all my time playing a Magic the Gathering Homebrew (Wagic) in stead of programming anything.