Radiometrix Ltd

USX2 Data Sheet

page 5

ccc

= a channel number from 00 to 127

aa

= a

two digit channel number from 00 to 15

nnnnn = synthesizer N register value, (up to 65535)

rrrrr

= synthesizer R register value, (up to 16383)

pp

= power setting value (0 - 30)

i

= table step (increments of N) (0-7)

ooooo = receive mode frequency offset

eee

= power calibration figure

N = channel frequency / (13MHz / R)

13MHz / R = 25KHz , so R = 520 (usually)

receive offset = 21.4MHz / (13MHz / R) , so = 856 (usually)

A pause of at least 50mS must be allowed after operations which result in eeprom programming operations

(all except NDIV, RDIV, GOTO, PSET and RSSI). This allows the programming cycle to complete.

Instructions marked ' # ' output a three byte ' OK<cr> ' sequence after sucessfully completing their eeprom

programming cycles

When first powered up, the unit will operate on channel and output level specified by the last CHAN and

POWER instructions, irrespective of previous NDIV, RDIV, CHAN or PSET operations)

3.

Short: A limited range of radio functions are controlled by sending a single byte to PO

0

- 127

select channel

(volatile)

128 - 159

select power

( = byte -128)

(volatile)

200

single read of RSSI

(output on P3)

201

single byte read, as for IDENT command

222

reception of 16 consecutive 222 bytes returns radio to

serial mode.

This mode of operation is intended to provide a simple, fast, serial command mode.

4.

Modem: Commands are interpreted as in SERIAL mode (and 'short' mode may be selected.) In this

mode the unit operates as a simple 1200 baud packet modem, with TXD (in) on P2 and RXD (out) on P1.

The N_TXE pin does not control tx switching in this mode, but rather the presence of valid data in the tx

buffer initiates a transmit burst. No handshaking is provided, and the unit has a sufficient over-link data rate

to transparently 'stream' continuous data. Error correction, re-transmission of corrupt packets and addressing

are not provided.

This mode is compatible with other Radiometrix 'i 1200' mode equipment, including the narrow band eval kit.

Notes:

Unlike in the RLC and TLC units, the LOCKSERIALMODE (and FAST) commands are non-volatile.

Once a serial mode is selected, the unit will power up in this mode until a PARALLEL command is

received.

The command interpreter IS case sensitive. Use upper case.

Spaces are optional (they are not decoded), provided the command line does not exceed 16

characters.

When manually programming this unit we recommend setting your terminal to local echo. The

'backspace' key functions normally.

All serial communications use 9600baud 'inverted RS232' 8 bit data, no parity, 1 start bit, 1 or 2 stop

bits

A simple 'driver' program will be made available to simplify programming of these units, if desired.

RSSI read operations only function correctly if the unit is in RX mode (n_TXE pin is high or floating)