1.1.6 build fails on FC30

Hal Murray hmurray at megapathdsl.net
Fri Apr 17 05:13:24 UTC 2020

> Because RS232 signaling is negative logic.

That's what I used to think, but somebody corrected me many years ago.

The data is upside down but the control signals are not.

>From https://en.wikipedia.org/wiki/RS-232
under Voltage levels

For data transmission lines (TxD, RxD, and their secondary channel 
equivalents), logic one is represented as a negative voltage and the signal 
condition is called "mark". Logic zero is signaled with a positive voltage and 
the signal condition is termed "space". Control signals have the opposite 
polarity: the asserted or active state is positive voltage and the de-asserted 
or inactive state is negative voltage. Examples of control lines include 
request to send (RTS), clear to send (CTS), data terminal ready (DTR), and 
data set ready (DSR).

These are my opinions.  I hate spam.

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