psf21911 ETC-unknow, psf21911 Datasheet - Page 87

• Manufacturer Part Number: psf21911
• Description: Isdn Echocancellation Circuit Terminal Applications Iec-q
• Manufacturer: ETC-unknow

PSB 21911
PSF 21911
Access to IOM-2 Channels
Figure 30 Monitor Channel Protocol
Before starting a transmission, the microprocessor should verify that the transmitter is
inactive, i.e. that a possible previous transmission has been terminated. This is indicated
by a "0" in MOSR:MAC, the Monitor Channel Active status bit.
To enable interrupts for the transmitter the MOCR:MXE bit must be set to “1“ (For details
see section 4.1.1 on page 115). After having written the Monitor Data Transmit (MOX)
register, the microprocessor sets the Monitor Transmit Control bit MXC to "1". This
enables the MX bit to go active (“0“), indicating the presence of valid Monitor data
(contents of MOX) in the corresponding frame. As a result, the receiving device stores
the Monitor byte in its Monitor Receive (MOR) register and generates an MDR interrupt
status.
Alerted by the MDR interrupt, the microprocessor reads the Monitor Receive (MOR)
Semiconductor Group
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