Register Description
Value after reset: 48
7
H
0
XDOV XFW XRNR RRNR MBR MAC1 BVS MAC0
XDOV Transmit Data Overflow
More than 32 bytes have been written in one pool of the XFIFO, i.e. data has been
overwritten.
XFW
Transmit FIFO Write Enable
Data can be written in the XFIFO. This bit may be polled instead of (or in addition to)
using the XPR interrupt.
XRNR Transmit RNR. Used in auto-mode only
In auto-mode, this bit indicates whether the ISAC-S receiver is in the "ready" (0) or
"not ready" (1) state. When "not ready", the ISAC-S sends an RNR S-frame
autonomously to the remote station when an I-frame or an S-frame is received.
RRNR Receive RNR. Used in auto-mode only
In the auto-mode, this bit indicates whether the ISAC-S has received an RR or an
RNR frame, this being an indication of the current state of the remote station: receiver
ready (0) or receiver not ready (1).
MBR
Message Buffer Ready
This bit signifies that temporary storage is available in the RFIFO to receive at least
the first 16 bytes of a new message.
MAC1 MONITOR Transmit Channel 1 Active (IOM-2 terminal mode only)
Data transmission is in progress in MONITOR channel 1.
BVS
B-channel valid on SIP (IOM-1 mode only). B channel on SIP (SLD) can be accessed.
MAC0 MONITOR Transmit Channel 0 Active. Used in IOM-2 mode only.
Data transmission is in progress in MONITOR channel 0.
Semiconductor Group
202