Question about modems

Nigel Johnson nw.johnson at
Wed Nov 13 12:13:18 CST 2019

Not much in the manual.  I browsed it looking for anything about data 
bits and stop bits. Nothing.

p1-2: ' Commands given to the Smartmodem must be ASCII coded at baud 
rates between 110 baud and 1200 baud. Once 'on-line', any code at any 
speed from 0 to 300 baud may be used.'

p 9-1 'Do not send any data to the Smartmodem while it is in local 
command mode unless the data is intended to be a command. Random data 
can confuse the baud rate detector and the command decoder giving 
unpredicatable results.'

That is al lI can find i nthe manual.



On 13/11/2019 12:39, Jim Brain via cctalk wrote:
> On 11/13/2019 5:31 AM, Nigel Johnson via cctalk wrote:
>> I actually have an original Hayes 300 modem. Would it be any use if I 
>> could set it up for a a test, or would it need another genuine Hayes 
>> one to talk to for what you need?
> I looked at the SmartModem 300.  It looks like it completely detected 
> the speed and parity internal to the unit.  If you have a manual or a 
> link ot one to validate, I think that would suffice. If it did do 
> that, then it would have reconfigured itself to match the terminal and 
> thus all communication would be in the same format (8N1, 7E1, etc).
> I did a quick check for an online manual, but my Google-fu is weak today.
> Jim

Nigel Johnson

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