peb20560 Infineon Technologies Corporation, peb20560 Datasheet - Page 217

• Manufacturer Part Number: peb20560
• Description: Dsp Oriented Pbx Controller Doc
• Manufacturer: Infineon Technologies Corporation

need not be set. If CMDR:XME is not set, the SACCO will repeatedly request for the next
data block by means of a XPR-interrupt as soon as the CPU accessible part of the XFIFO
is available. This process will be repeated until the CPU indicates the end of message
per command, after which frame transmission is ended by appending the CRC and
closing flag sequence.
If no more data is available in the XFIFO prior to the arrival of XME, the transmission of
the frame is terminated with an abort sequence and the CPU is notified per interrupt
(EXIR:XDU). The frame may also be aborted per software (CMDR:XRES).
Figure 3-4 outlines the data transmission sequence from the CPU’s point of view:
Figure 3-4
Semiconductor Group
Command
XTF or XDD
Interrupt Driven Transmission Sequence (Flow Diagram)
N
N
(up to 32 Bytes)
Write Data
to XFIFO
XTF/XPD or XDD
Command XME+
Pool Ready
Massage
Transmit
START
End of
END
?
?
3-11
Y
Y
ITD05847
XFW Bit in STAR Register
XPR Interrupt or Set
Operational Description
PEB 20560
2003-08