PEB2085 SIEMENS [Siemens Semiconductor Group], PEB2085 Datasheet - Page 72

• Manufacturer Part Number: PEB2085
• Description: ISDN SubscribernAccess Controller
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

Figure 36
Examples of MONITOR Channel Applications in IOM
The MONITOR channel operates on an asynchronous basis. While data transfers on the bus
take place synchronized to frame sync, the flow of data is controlled by a handshake procedure
using the MONITOR Channel Receive (MR0 or 1) and MONITOR Channel Transmit (MX0 or
1) bits. For example: data is placed onto the MONITOR channel and the MX bit is activated.
This data will be transmitted repeatedly once per 8-kHz frame until the transfer is
acknowledged via the MR bit.
The microprocessor may either enforce a "1" (idle) in MR, MX by setting the control bit MRC1,
0 or MXC1, 0 to "0" (MONITOR Control Register MOCR), or enable the control of these bits
internally by the ISAC-S according to the MONITOR channel protocol. Thus, before a data
exchange can begin, the control bit MRC(1, 0) or MXC(1, 0) should be set to "1" by the
microprocessor.
The MONITOR channel protocol is illustrated in figure 37. Since the protocol is identical in
MONITOR channel 0 and MONITOR channel 1 (available in TE mode only), the index 0 or 1
has been left out in the illustration.
The relevant status bits are:
In addition, the status bit:
MONITOR Channel Active MAC (MAC0, MAC1)
indicates whether a transmission is in progress (Register: STAR).
Semiconductor Group
for the reception of MONITOR data, and
for the transmission of MONITOR data (Register: MOSR)
IOM -2
MONITOR Channel Data Received MDR (MDR0, MDR1)
MONITOR Channel End of Reception MER (MER0, MER1)
MONITOR Channel Data Acknowledged MDA (MDA0, MDA1)
MONITOR Channel Data Abort MAB (MAB0, MAB1)
R
ITAC
V/D - Module
R
C µ
PSB
2110
Data Communication (MONITOR1)
ARCOFI
ARCOFI
V/D - Module
72
R
-SP PSB
R
PSB
2160
2165
Control (MONITOR1)
®
-2 TE Mode
Functional Description
PEB
ISAC -S
2085/86
µC
R
ITS00869