Rabbit EM1500, Руководство по эксплуатации продукта

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EM1500 User’s Manual
www.rabbit.com
43
Character size
This is the number of bits per character, not counting start, parity or stop bits. The
only valid entries for this field are 7 and 8.
Parity
Parity is the simplest way to check that transmitted data was received without errors.
The options are:
• None: no parity check is done.
• Space: the parity bit is always zero.
• Mark: the parity bit is always one.
• Odd: data bits plus the parity bit equals an odd number
• Even: data bits plus the parity bit equals an even number
“Space” and “Mark” are seldom used parity methods because they are less likely to
reveal the existence of a garbled bit. Using “Odd” or “Even” for parity is more com-
mon. If you want 2 stop bits (only 1 stop bit is supported in the hardware), you may
simulate it in software by choosing “Mark” for parity. This looks like an extra stop bit
in the data stream.
NOTE: Data bytes received with parity error are not transmitted to the peer.