TM8000 3DK Hardware Developer’s Kit
Application Manual
Programmable I/O Lines
71
September 2003
© Tait Electronics Ltd
3.2.3
Channel Locked Status
Application
This output signal is used to indicate the frequency lock status of the
synthesizer and is constantly activated during normal operation. The output
is deactivated, if the radio synthesizer is unable to “lock” to the current
channel frequency, which can be caused by a hardware fault.
The deactivation of this output always coincides with the “OL” (out of
lock) control head display.
Note
During channel change, although the synthesizer has to re-syn-
chronise with the new channel frequency, this output will not be
temporarily deactivated.
Configuration
Configure an output line and associate it with this action. Set the active state
to be high or low (as required).
Timing
The maximum time out of lock before this action is activated (e.g. during
channel change) is 50ms.
Description
When the radio detects a change of the synthesizer lock detect state, the
radio sets the state of this output line to reflect the lock detect state. When
the synthesizer is locked, the output line is active. When the synthesizer is
not locked, the output line is inactive.
Related Actions
None.
3.2.4
Reflected PTT Status
Application
This action is used to report the PTT status by generating a logic OR of all
PTT sources programmed to reflect their status. The priority does not affect
the logic OR.
Configuration
1.
In the PTT form, configure the ‘PTT State is Reflected’ check box
for each PTT type.
2.
In the Programmable I/O form, configure an output line and
associate it with this action. Set the active state to be high or low (as
required).
Timing
The response time of this output line is less than 2ms.
Description
When the radio detects a change in PTT state, it sets the state of this output
line to reflect the PTT state. When any PTT state changes to active, the
output line is active. When all PTT states change to inactive, the output line
is inactive.
Related Actions
The external PTTs can be monitored directly by the external application.