ISDN Data and Telephony Protocol Engine (inc. X.25)
CMX228
1.5.9 Hardware Description
1.5.9.1 LED Status Indicators (LED1 to LED9, and ILFI)
LED1 (HK1) is low when the POTS port is off-hook, high when on-hook.
LED2 (AA) indicates that register S0 has been set to 1 or more when low and set to 0 when high
(RS232 Auto Answer indication).
LED3 (DCD) is low when a call is connected via the RS232 port (if &C0 is set to '1'), high when a call
is not connected to this port.
LED4 (RTS) is low if RTS on the RS232 port is active and vice versa, indicating flow control (RS232
Ready To Send).
LED5 (RXD) is low if data is being sent to the DTE (RS232).
LED6 (TXD) is low if data is being received from the DTE (RS232).
LED7 (DTR) is low if the de-bounced DTR line on the RS232 port is active and vice versa.
LED8 (AR) is pulsed high and low until the ISDN line is activated, when it remains low constantly.
LED9 (CN1) is high when the POTS port is connected to the ISDN network, low when not connected.
ILFI is high when an ISDN Link Failure is Indicated, low when the link is operational.
The functions of the LED and ILFI indicators are set out in the table below:
Pin No. Designation
POTS port
RS232 port
12
13
14
15
16
17
18
19
21
54
LED1
LED2
LED3
LED4
LED5
LED6
LED7
LED8
LED9
ILFI
Off-Hook
~
~
~
~
~
~
Auto-Answer
Carrier Detect
Ready to Send
Receive Data
Transmit Data
Data Terminal Ready
ISDN Line Activated
~
~
ISDN Line Activated
Call Connected
ISDN Line Failure
Indicator
ISDN Line Failure
Indicator
ã 1999 Consumer Microcircuits Limited
ã 1999 Chiron Technology Limited
30
D/228/1
CMLMICRO [ CML MICROCIRCUITS ]
