Registered: Nov 1999
Location: Columbus In USA
Posts: 18

As the maker of the Bridge for the Palm V and Palm III, I have had many questions regarding the possibility of a Bridge for the Visor.

We have done quite a bit of research and have decided that we will not be making a Bridge for the Visor.

The mechanical differences aside, there are some electrical issues. The Palm has 4 dedicated transmission lines to the cradle connector. The Visor has 2. If the Palm accessory that you want to mate with the Visor uses 4 transmission lines, it won't work.

It is also questionable if just using the Bridge to sync the Visor in a Palm cradle would work. The Palm cradle connects pins 2 and 7 together completing a circuit and reads pin 8 to ID the module connected, (modem or hotsync). The Visor had no ID capability at all. It shorts a couple pins to ground to initiate a sync. In addition, the voltage levels on the Visor's serial port are not RS232 compatible. (The voltage conversion is done in the Visor's cradle).

I wish we could make a Bridge product for the Visor, but it's not going to work. In fact, I ordered 2 Visors a couple weeks ago, and you can get the serial cradle for only $20 extra. (So why buy a Bridge for $15?)

Anyway, I wanted to post this because we have received so many emails about it.

Regards,

Don Damiani
Vice President
Midwest PCB Designs

Registered: Sep 1999
Location: Sydney Australia
Posts: 1883

Hi Don,

Thanx for your posting!
It's cool to see that manufacturers are using this forum too to post messages.

Too bad you won't be making the bridge, but I understand why.

Let us know If you company is planning to make any other add-on for the visor.

Registered: Oct 1999
Location: Maplewood, NJ USA
Posts: 48

Hey, is it just me or does anyone else now know what the bridge is? HELP...what is it?

Mike

------------------
Life moves pretty fast. If you don't stop and look around once in a while, you could miss it.
-Ferris Beuler

Registered: Nov 1999
Location: Columbus In USA
Posts: 18

Well, since you asked...

The Bridge comes in 2 . One mates with Palm Pro or Palm III, the other mates with Palm V. Both are designed to fit on the Palm Pro cradle connector, which is the same connector used on the Palm III.

So, using the Bridge, if you had both , you could sync a Palm Pro, a Palm III, and a Palm V in the same cradle. (A Palm Pro or Palm III, not the Palm V cradle.)

In addition, you can use the Bridge to attach your Palms to many Palm Pro or Palm III accessories. So instead of buying a new GoType, you can use the Bridge and still use the Palm V with it.

Check our web site for all the poop!
www.midwestpcbdesigns.com

Don

Registered: Sep 1999
Location: VA, USA
Posts: 27

The bridge is a hardware product, right?

Why can't the Visor -> PalmIII bridge be a springboard? Sure, you would have to sync it upsidedown, but I expect it would more offen be used to hook up cell phones and stuff like that.

The hardware shouldn't be a whole lot more then a UART and a ROM. That'll be more costly then a cable, but it still wouldn't break the bank.

Registered: Jan 2000
Location:
Posts: 391

(This message is also emailed to Don Damiani in response to a message he sent pointing me at this thread)

RTS and CTS aren't connected to UARTs. To get any reasonable speed through them you'd have to write a bit-banger software UART, which would lock up the user interface. So I doubt very much whether any module uses them for anything but flow control.

90% of the uses will be satisfied by looping RTS back to CTS on the module side. You can hotsync that way (after all, the Visor serial cradle does). Other software will have to use XON/XOFF flow control, but they have to support that anyway for 3-wire serial connections.

* The Visor uses pin 2 (HS2, KBD) to ID the module (keyboard or hotsync). It seems to function similarly to pin 8 (GPI2) on the Palm, but in the reverse sense... you pull it to ground to enable hotsync, rather than pulling it high to enable a modem. For cradle purposes a resistor should do the trick, but I'm going to stick a SPST toggle switch in there in my own hack, along with a momentary from ground to HS1.

As for why we'd buy one when we have the serial cradle... the cradle is not usable for walking-around use (with a modem or serial cable).

I've ordered the parts and I'll be building my own adaptor for my own use, using the information in the following threads:
http://discussion.visorcentral.com/...TML/000090.html http://discussion.visorcentral.com/...TML/000436.html

Please reconsider. I'm going to end up paying well over twice the price of a Bridge to get only part of the functionality, and so are the other people involved in this thread.