[time-nuts] Nortel Trimble thunderbolt

Ed Palmer ed_palmer at sasktel.net
Sat Jul 6 13:17:33 EDT 2013


Have you put a scope on the Nortel's transmit lead?  If it happens to be 
putting out data you can at least determine the baud rate and whether 
it's TTL or RS232 levels.  It might put out some kind of startup message 
on powerup.

Ed

On 7/6/2013 10:56 AM, Jim Sanford wrote:
> All:
>
> This is still not going well.
>
> I have tried 3 different computers, 2 running Win7 and one running 
> XP.  the XP machine successfully controls an Icom radio on the same 
> port, so I know the port is good.  I have tried a new serial cable. I 
> have tried with and without a null modem.
>
> No matter what I do, Lady Heather reports no serial communications on 
> comm/x.
>
> /Thanks & 73,
> Jim
> wb4gcs at amsat.org
> /
> /
> On 7/6/2013 10:44 AM, Ed Palmer wrote:
>> Certainly if you need a full implementation with various control 
>> leads you might have to dig out the breakout box and figure it out. 
>> But the volts / no volts idea is still useful for connecting pairs 
>> like RTS/CTS or DSR/DTR.  But I'm surprised how many devices don't 
>> use the control leads.  Most of the devices I work with don't even 
>> use software flow control.
>>
>> Ed
>>
>> On 7/5/2013 10:06 PM, Chris Albertson wrote:
>>> On Fri, Jul 5, 2013 at 7:03 PM, Ed Palmer <ed_palmer at sasktel.net> 
>>> wrote:
>>>
>>>> I always cursed when I tried to figure out how to wire an RS232 cable
>>>> until I realized that transmit had a voltage on it while receive 
>>>> was close
>>>> to zero volts.  So now I just remember that volts on one end 
>>>> connects to no
>>>> volts on the other end.  Works every time and I don't have to think 
>>>> about
>>>> straight or cross-over.
>>>
>>> That only works if there are only three wiresand no handshaking.  
>>> What if
>>> there is DTE/DCE and so on?
>>>
>>> But I think in this case it is just a three wire connection but 
>>> still there
>>> is room for errors like for example is one of them a TTL level and the
>>> other RS-232.  Some times you can mix the two, sometimes not.


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