Radiometrix Ltd

USX2 Data Sheet

page 4

USX2 serial interface details (version 4):

PRELIMINARY

The USX2 user interface is accessed through the four parallel pins (P0/serial through P3).

It has four operating modes:

1.

Parallel: Frequency of operation is selected as one of 16 (chans 0-15), by means of a 4 bit inverted value

applied to P0-P3. The P0 pin will also respond to a LOCKSERIALMODE datastream (inverted rs232, 9600

baud), which will cause the radio to enter

serial mode. In parallel mode, the IDENT command string is still

decoded, but the unit remains in parallel mode.

2.

Serial: Frequency of operation, radio set up, power output and various other parameters are controlled by

command strings sent to P0. Pin P3 functions as a 'readback' port while P1,2 are not used in this mode.

In this mode, decimal values are used (to simplify direct manual programming via a terminal)

Commands include :

:

empty command buffer

? or /

read back buffer contents

<

backspace>

delete last character

<

cr>

process buffer

PARALLEL

return to the basic,

parallel mode (and turn modem off)

DUMP

read back contents of eeprom (output on P3)

MODEM

activate 1200 baud modem

#

NOMODEM

de-activate 1200 baud modem

#

DEFCH

ccc

set default channel

(non-volatile)

#

DEFPOW pp

set default tx power

(non-voltatile)

#

CHAN

ccc

jump to channel

(volatile)

POWER pp

select tx power

(volatile)

RSSI

single read of RSSI

(output on P3)

SHORT

enter

short command mode

#

(The following commands are used to set up the radio operating characteristics, and should be viewed with

caution. Especially the CALPOWER command, which initiates a multiple write operation to the power

calibration table )

NDIV

nnnnn

force N divider value

(volatile)

RDIV

rrrrr

force R divider value

(volatile)

RLOAD

rrrrr

Set R divider value

#

OFFSET ooooo

Set RX offset

#

LOAD aa nnnnn

Set N values for first 16 channels

#

START

nnnnn

Set N value for ch 16

#

STEP

i

Set increment for table

#

LIMIT

ccc

Set highest permitted channel number

#

SETPOW eee

Set maximum power output (100mW)

CALPOWER (etc)

(see factory procedures for more details)

TEST

Generate a 250Hz test modulation

(only fuctions in TX mode, cancelled by sending a <cr> byte)

IDENT

Readback a single byte, depending on current mode:

Parallel:

P

Serial

S

Short

1

Modem

M

(Channels 0-15 are individually programmed by the

LOAD operation. Channels 16-127 are a consecutive

table, using the

START value as a start point (=channel 16) and increasing the N value by STEP with each

increase in channel number)