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Elmos Semiconductor AG

Data Sheet

QM-No.: 25DS0046E.03

PRODUCTION DATA - JAN 15, 2015

Elmos Semiconductor AG reserves the right to change the detail specifications as may be required to permit improvements in the design of its products.

KNX/ EIB TRANSCEIVER

E981.03

Activation

Analog Mode is activated if

•

no higher prioritize mode is active (e.g. reset,

starup) and the baud rate select pins BS0 and BS1

have both high level

Deactivation

Analog Mode will be left for

•

a higher prior mode (e.g. reset) if the activation

condition for that modes holds or

•

Normal Mode if any of the baud rate select pins has

low level

Activation

Monitor mode can be activated if

•

no higher prioritize mode is active (e.g. reset,

startup, busy) and

•

the CMODE register has the Bus monitor mode

value

The CMODE register can be modified by

•

sending a U_ActivateBusmon service request via

UART or

•

writing to the CMODE register via SPI or UART

Deactivation

Bus monitor mode can be left for any higher prioritize

mode (e.g. reset) if the activation condition for that

modes holds.

Switching to Busy Mode is not possible in Bus monitor

mode.

Properties

•

The data link layer of the UART is in bus monitor

mode. Only the local L_Busmon service is available

for the host processor. All L_Data host to E981.03

services including L_Poll_Data service are not avail-

able and will be ignored.

•

Each byte received on the KNX / EIB is sent to the

host as well as illegal control bytes and all acknowl-

edge frames.

6.5 Analog Mode

Properties

•

IC is fully functional (all supplies active)

•

host UART interface is switched off.

No UART service is available

•

bypass from KNX transceiver to UART transceiver

is active

•

host SPI interface is active (may be switched off by

host processor)

comparable to 'Medium Attachment Unit (MAU)'

KNX standard: Volume 3 System Specifications: Physical Layer

General

6.6 Monitoring Mode

•

E981.03 is quiet (not sending) on the KNX bus.

•

Writing to the telegram buffers in Bus Monitoring

Mode is possible.

•

The transmit frame buffer content will not be trans-

mitted to the KNX bus in Bus Monitoring Mode.

•

U_Reset.request clears the transmit buffer ready

flag (Flag READY in Register KNX_TR_BUF_STAT).

Leaving Bus Monitoring Mode without clearing this

flag results in transmission of the transmit buffer

content on KNX bus.

•

Alarm telegrams can be transmitted even in Bus

Monitor Mode.

All received telegrams are sent byte-wise from E981.03

to the host.

Switching to Busy Mode is not allowed in Bus Monitor-

ing Mode. Bus Monitoring Mode will be deactivated on

activation of Busy Mode.

It is recommended to activate and deactivate Bus Mon-

itoring Mode using UART service requests. Activation

using direct register access will be described in an ap-

plication note.