Thursday, April 17, 2003

James Wiebe of WiebeTech has written an excellent, if somewhat academic, description of FireWire port destruction and its root causes.

About five months ago I privately implored James to publicly document the over-voltage protection they had quietly rolled into their Super Drive Dock, a feature which soon spread through their product line. While I'm disappointed they didn't release a dedicated press release on the topic, it is mentioned in this white paper. However James, being more of a gearhead than a PR maven, hid this nugget under section 5.2.2, Voltage Transient Suppression Circuitry On Bus Powered Devices:

WiebeTech has implemented a proprietary technique which prevents transients at power on time from being transmitted to the host computer via the Data lines. This resolves issues related to use of bus powered devices. This technique has been used with excellent results in WiebeTech's bus powered FireWire DriveDock devices, which are capable of bus powering 3.5 inch IDE hard drives.

.... [ Tales from the Red Shed]

Quite some time ago, I wrote about a silly little trick that would allow you to power your iPod from your computer without causing the iPod to be detected/mounted by the computer. Useful for listening to the output off computer power when the iPod's battery is dead.

Now, the key to that hack is that two of the six pins on the firewire port are longer than the others. These two pins are the power pins. On most cables, the same two pins are longer.

End result: when you plug a firewire cable into a device, the first thing to be connected are the power pins, including the ground. The minor delay between that connection and the data pin connection (likely a few milliseconds) should be enough to allow the bus to settle and not cause the surge as described by WeibeTech's excellent article.

It would be interesting to know if all firewire cables are created equal. Very unlikely. I wonder if there are a bunch of firewire cables that do not have longer power pins floating around? Similarly, are all drive/computer firewire ports created equal? Of course, if you stick the connector in at enough of an angle into a "loose" firewire jack, that might be enough to cause a problem, as well.

2:46:12 PM  pontificate    

Last August, I wrote about Ollo: The Sunny Valley Fair. Ollo is a wonderful game that my son-- Roger-- still digs. However, he has started to outgrow the game a bit (or is simply bored with it).

While shopping in Staples or CompUSA-- I can't remember which-- we found Freddie Fish: The Case of The Haunted Schoolhouse bundled in with Freddie Fish 4. It was on the discount table and was marked down to $7!

Of course, the game is old enough that I had to dig out the OS 8.6 CDs that shipped with the iMac to make it work. It was worth it. Definitely a brilliant game. Since Roger is totally obsessed with fish anyway, the fish theme is a huge hit. Hours of entertainment.

Like Ollo, Freddie is a multi-screen game with simple point and click interaction. You navigate from area to area by clicking on hot spots. Within any screen, there are many hot spots that produce funny animations, games, learning activities, or continue the story.

Great stuff.

It appears that Humongous Entertainment has been absorbed by Infogrames Kids. I can't find all of the Freddie titles on the new site and I have no idea if what is available is a re-release that addresses the compatibility issues.

In any case, if you have a machine that can boot OS 8.6, Ollo and Freddie are truly wonderful games for any kid that has enough coordination to deal with the mouse. In my case, I have an original iMac DV that has been dedicated to the task of playing Ollo and Freddie.

Apparently, InfoGrames thinks kids are learning more slowly than Humongous did. Under the Humongous logo, Freddie 2 was listed as for kids of age 3 to 8. Infogrames has narrowed that to 4 to 7. Odd.
1:03:04 PM  pontificate