PEB 2091
PEF 2091
Functional Description
IOM R -2 Frame
No.
1
2
3
4
5
6
7
1
0
MX
EOM
DIN
1
0
MR
MX
MR
1
0
DOUT
1
0
Abort Request from Receiver
ITD04231
Figure 29
Abortion of Monitor Channel Transmission
Example: Standard Transmission Procedure in stand-alone mode
1. The first byte of monitor data is placed by the external controller (e.g. ICC, EPIC®) on
the DIN line of the IEC-Q and MX is activated (low; frame No. 1).
2. The IEC-Q reads the data of the Monitor Channel and acknowledges by setting the
MR-bit of DOUT active if the transmitted bytes are identical in two received frames
(frame No. 2 because the IEC-Q reads and compares data already while the MX-bit
is not activated).
3. The second byte of monitor data is placed by the controller on DIN and the MX-bit is
set inactive for one single IOM®-2-frame. This is performed at a time convenient to the
controller.
4. The IEC-Q reads the new data byte in the Monitor Channel after the rising edge of MX
has been detected. In the frame immediately following the MX-transition
active-to-inactive, the MR-bit of DOUT is set inactive. The MR-transition
inactive-to-active exactly one IOM®-2-frame later is regarded as acknowledgment by
the external controller (frame No. 4–5).
The acknowledgment by the IEC-Q will always be sent two IOM®-2-frames after the
activation of a new data byte.
5. After both monitor data bytes have been transferred to the IEC-Q, the controller
transmits "End Of Message" (EOM) by setting the MX-bit inactive for two or more
IOM®-2-frames (frame No. 5–6).
6. In the frame following the transition of the MX-bit from active to inactive, the IEC-Q
sets the MR-bit inactive (as was the case in step 4). As it detects EOM, it keeps the
MR-bit inactive (frame No. 6). The transmission of the monitor command by the
controller is complete.
7. If the IEC-Q is requested to return an answer it will commence with the response as
soon as possible. In case the "monitor time-out" function is enabled it may have to
Semiconductor Group
79
Data Sheet 01.99
INFINEON [ Infineon ]
