TM8000 3DK Hardware Developer’s Kit
Application Manual
Description of the Radio Interfaces
35
September 2003
© Tait Electronics Ltd
Detection of
Control Head
When the TM8115 control head is not installed, the radio body will receive
no volume control level or power on/off signal from the control head.
In order for the volume control default to work properly, the absence of a
control head is detected by detecting the absence of the volume
potentiometer.
For operation with the TM8105 blank control head, the radio must be
programmed always to power up when power is applied and the ignition-
sense hardware link LK1 must be fitted. For more information on hardware
links refer to
“Power Sense Options” on page 121
.
Table 2.23
Control-head connector - data characteristics
Parameter
Standard
Test method and conditions
Comments
min.
typ.
max.
units
Serial port
Baud rate:
1200, 2400, 4800,
9600, 14400, 19200
bit/s
All UART parameters are fixed
and common to all UARTs
except for the baud rate
which is configurable and
different for different modes/
applications
Data bits:
8
Start bit:
1
Stop bit:
1
Parity:
None
Protocol:
RPI
CCDI2
Flow control:
Software
XON/XOFF
GPIO
Delays:
I/O mirror to IOP
UI key delay
500
50
µs
ms
Table 2.24
Speaker frequency response plot