News from Mac OSX - Mysterious Serial Port

[Dar Scott]

On Thursday, August 21, 2003, at 01:35 PM, R. Hillen wrote:

> On my Mac G4 I use the GPort from GriffinTechnologies, which replaces 
> the build in modem.

> To read the sent serial data I used a Windows Hyperterminal running on 
> a Win-Laptop.

> I typed "1234567890" and got two garbage chars
> I again typed "1234567890" and got two garbage chars
> I again typed "1234567890" and got about 12 garbage chars.

> I typed "1234567890123456789012345678901234567890 1234567890" and got:
> "12345678901234567890123456789012345678901234567890", followed by 
> NewLine.

OK.  My curiosity got the better of me.  I looked at the Griffin 
Technology web site.

The gPort seems to have a classic DIN serial port.  Is that what you 
have?  Or am I looking at the wrong thing?  This is not RS-232.  
However, it is normally possible to wire it to a Windows Laptop RS-232 
port so that it will (barely) communicate, however.  How do you have 
that wired?

It is also possible to make a loop-back circuit so that you can read 
what you write.  You might even still be able to buy one.  If you have 
any old Mac serial cables, you can make one from that.  I can provide a 
stack that will help in testing that.

You might have an old modem in your junk box that takes the levels from 
the classic Mac serial port.  You can try talking to that.

Dar Scott

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