SAB 82525
SAB 82526
SAF 82525
SAF 82526
2.7 Transmit Data Flow
Two different types of frames can be transmitted:
– I-frames and
– transparent frames
as shown below.
Ι
FLAG
ADDR
CTRL
CRC
FLAG
ADDRESS
CONTROL
DATA
CHECKRAM
*1
Transmit
Transparent
Frame
XFIFO
(XTF)
XFIFO
*1
Transmit
I-Frame
(XIF)
XAD1
XAD2
ITD00229
*1 Optional checkram handling in version 2 upward
Figure 9
Transmit Data Flow of HSCX
For I-frames (command XIF via CMDR register), the address and control fields are generated
autonomously by the HSCX and the data in the XFIFO is entered into the information field of
the frame. This is possible only, if the HSCX is operated in the auto-mode.
For transparent frames (command XTF via CMDR register), the address and the control fields
have to be entered in the XFIFO as well. This is possible in all operating modes and used also
in auto-mode for sending U-frames.
Semiconductor Group
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SIEMENS [ Siemens Semiconductor Group ]
