STE sas Milano - ITALY
Pag. 10 of 14
PRO, PRI ( J1 pins n.12-13) programming input-output
CH A-B-C-D ( J1 pins n.14-15-16-17) channel select input
PRI and PRO are connected to the IC10 microcontroller USART input-output
( see block diagram Fig.2 ) and are used to program the transmit and receive frequencies and
the TX output RF power ( “High” or “Low” ).
Refer to Fig.5 for the programming set-up.
Sixteen channels can be programmed and stored in the IC10 EEPROM memory.
In operation one of the 16 channels is selected using parallel control lines CHA, CHB, CHC
and CHD ( negative logic).
The transceiver can be also programmed (Through PRI and PRO) during normal operation on
default channel n.1 .Serial mode programming software is available for the BK7XX
transceiver – for further details contact the STE sales office.
TABLE 1
CHANNEL
CHD
CHC
CHB
CHA
1 1 1 1 1
2 1 1 1 0
3 1 1 0 1
4 1 1 0 0
“ “ “ “ “
“ “ “ “ “
15 0 0 0 1
16 0 0 0 0
Note : CHA-CHB-CHC-CHD inputs have internal pull-up (10 K
Ω
) to + 5 V.
IC10 (see Fig. 2) is a PIC16F870 flash microcontroller whose function is to control the general
functions of the transceiver and to program the channel frequency ( transmit or receive ) in the
“PLL” integrated circuit ( IC11 –Fujitsu MB15E03SL ).
The microcontroller has inside an EEPROM where are stored program configurations for up to 16
channels ( transmit and receive frequency, in 12.5 KHz step , and RF output power ).
One of these 16 channels is selected using parallel control lines via the terminals CHA,CHB,CHC
and CHD of J1 connector