Serial interface commands
The internal firmware for TLM2 has two versions.
Version 1 is IDENTICAL to our standard LMT2-458-5 (100mW) in all respects
Version 2 is specific to paging applications.
Version 1: programming instruction
2400 baud RS232. 8 bit data, no parity, 1 start bit, 1 or 2 stop bits.
Serial data is sent to the unit on one of the parallel channel select pins (P0). It is very important that the unit
does not 'decode' switch bounce in ordinary operation as a command string, or spurious re-writing of the
e2prom will result. For this reason the user must send the 16 character string ENABLESERIALMODE
(followed by a carriage return) to activate the serial command mode before sending any of the command
strings listed below. Command mode is disabled on power down, or on reception of a # character. To
successfully program the unit, it must be enabled ('RXE high (rx) or TXE low (tx)).
GOCHAN aa
LOAD aa nnnnn
SETPAR
Serially select channel aa, where aa is ch0 to ch31
Set value of N register for channel aa, where aa is Channels 0 to 31
Channel selected by 4 bit parallel inputs (ch0 to ch15 only)
Channel selected by most recent GOCHAN operation
Set value for R register
SETSER
RVALUE rrrr
SINGLE nnnnn
Set value of N for single channel operation.
N value NOT stored in EEPROM
<cr>
Process entry
/
Clear all buffers
#
Disable command mode
aa = a two digit channel number from 00 to 31
nnnnn = synthesizer N register value (up to 65535)
rrrr = synthesizer R register value (up to 16383)
fRF
458.525MHz
25kHz
N =
R =
=
= 18341
fChannelspacing
fTCXO
13MHz
25kHz
=
, So R=520
fchannelspacing
Note: A pause of at least 50ms must be allowed between command strings (EEPROM programming time).
SINGLE mode does not store the N value in EEPROM. Therefore the unit is inoperative after a
power down until either another valid SINGLE command is received, or mode is changed by a
GOCHAN, SETPAR or SETSER command. SINGLE mode is intended for frequency agile
applications.
Radiometrix Ltd
TLM2 Data Sheet
page 4
RADIOMETRIX [ RADIOMETRIX LTD ]
