W6691CD WINBOND [Winbond], W6691CD Datasheet - Page 94

• Manufacturer Part Number: W6691CD
• Description: ISDN S/T Interface Transceiver
• Manufacturer: WINBOND [Winbond]

RBC7-0
Used in transparent mode only. Eight least significant bits of the total number of bytes are in a received frame.
These bits are valid only after a RME interrupt and remain valid until the frame is acknowledge via the RACK
bit.
8.11.13 B1_ch Receive Frame Byte Count High B1_RBCH
Value after reset: 00H
LOV
Used in transparent mode only. A "1" in this bit indicates a received message
only after RME interrupt and is cleared by the RACK command.
RBC12-8
Used in transparent mode only. Five most significant bits of the total number of bytes are in a received frame.
These bits are valid only after a RME interrupt and remain valid until the frame is acknowledge via the RACK
bit.
Note: The frame length equals RBC12-0. This length is between 1 and 8191. After a RME interrupt, the
number of data available in B1_RFIFO is frame length modulus threshold.
Remainder = RBC12-0 MOD threshold
No of available data = remainder
No of available data = threshold
The remainder equals RBC5-0 if threshold is 64.
8.11.14B1_ch Transmit Idle Pattern
Value after reset: FFH
IDLE7-0
This pattern is transmitted when the transmitter is active and transmit FIFO is empty. Valid in extended
transparent mode only.
IDLE7
7
0
7
Message Length Overflow
IDLE6
Receive Byte Count
6
0
6
Receive Byte Count
IDLE5
LOV
5
5
RBC12 RBC11 RBC10
IDLE4
4
4
IDLE3
3
3
if remainder
if remainder = 0
B1_IDLE
IDLE2
2
2
94
0 or
RBC9
IDLE1
1
1
Read/Write
IDLE0
RBC8
0
0
Read Address 5EH
Preliminary W6691
Publication Release Date: Sep 2001
Address 5FH
8192 bytes. This bit is valid
Revision 1.1