STE sas Milano - ITALY
Pag. 11 of 14
BK77x FREQUENCY-POWER PROGRAMMING
At “Power On” the radio memory ( IC10 EEPROM ) is loaded with the “ DEFAULT “
channels ( see Table 2 ).
The radio can be programmed on different RF channels ( TX frequency , RX frequency and
TX output power level ) via “PRI” and “PRO” terminals ( J1 connector ) connected to the
serial “COM ” port of a “PC”.
“PRI” and “PRO” pins must be connected respectively to the “TD” and “RD” lines of the
RS232 port with a suitable “TTL” to “RS232” driver ( fig. 10 ).
Data are exchanged between the radio and the “PC” as “ASCII” characters : programs such
as “HyperTerminal” can be used to send and receive the “ASCII” strings of characters.
Serial protocol format : 9600 Baud , 8 data bit , 1 stop , no parity .
Fig . 10 PC/RADIO programming with TTL/RS232 driver.
Each channel can be individually programmed on new frequencies ( and RF power level ) :
the new data will be retained into the radio memory (EEPROM).
At any time, if necessary, a “RESET” command reloads the memory with the “DEFAULT”
channels.
J1
2
1
3
5
7
9
11
13
15
17
19
12
20
PC PORT
GND
RS232
PRO
PRI
5 VDC
4,7K
10K
BC547
1N4148
10K
4,7K
4,7K
BC557
220
220
2,2K
22uF
-10 V
1N4148
TTL/RS232 DRIVER
RD
TD
GND
2
3
5
16V
47uF
10V
BK7XX