IBM DS-2000 warranty Data ready Indicates Is present Receive buffer

FUNCTIONAL DESCRIPTION

Bits BI, FE, PE, and OE are the sources of receiver line status interrupts. The bits are reset by reading the line status register . In FIFO mode, these bits are associated with a specific character in the FIFO and the exception is revealed only when that character reaches the top of the FIFO.

BI	-	Break	Interrupt:
		Indicates the receive data input has been in the
		spacing state (logic 0) for longer							than	one	full
		word	transmission		time.
	FIFO	mode:
		Only	one	zero character is loaded into the FIFO
		and	transfers are disabled				until SIN goes to				the
		m a r k s t a t e ( l o g i c 1 ) a n d a v a l i d s t a r t b i t i s
		received.
FE	-	Framing Error:
		Indicates the received character had an invalid
		stop	bit.	The	stop	bit following			the	last	data
		or parity bit was			a 0	bit (spacing level).
PE	-	Parity Error:
		Indicates		that	the	received		data	does	not	have
		the	correct parity.
OE	-	Overrun Error:
		Indicates		the receive buffer was not read before
		the	next	character was received and the						character
		is destroyed.
	FIFO	mode:
		Indicates		the FIFO is full and another character
		has been shifted in. The character in the shift
		register		is destroyed but			is	not	transferred to
		the	FIFO.
DR	-	Data ready:
		Indicates		data	is present		in	the	receive buffer
		o r F I F O .		D R i s r e s e t b y r e a d i n g t h e r e c e i v e

buffer register or receiver FIFO.

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