Integration Guide

SmallSTAR-Module 910
StarModulePlus910_1_3.d
oc
Preliminary
Confidential page 6 of 6
DATALOGIC PROPRIETARY INFORMATIONS
Absence of RF: high level.
Presence of RF: low level.
The RF down conversion starts with the reception of the 0xB2 (old protocol) or 0x96 (new protocol) byte,
followed by the packet length byte. According to this value the conversion goes on receiving length number
bytes plus the two CRCs.
Thus the byte stream presented on TX_DATA (output) UART starts with 0xFF, 0xB2 or 0x96, the packet
length byte and so on sending the number of length byte to complete the packet reception plus the CRCs
bytes.
Active blocks are:
 Receiver part of transceiver
 ADC conversion of RSSI signal
 DSP of the analog demodulated signal in order to decide the best RX frequency out of the 2 available
 Analog signal conditioning block, prior to ADC conversion
 ADC conversion of temperature indication and compensation
 UART to receive command strings from the host @38400, N, 8, 1 on pin Data In.
The reception of the enter test string [ESC]#+CMD[CR] causes the exit from RX mode and the entering of
CMD mode, while the reception of the TX command [STX] [DATA] causes the exit from RX mode and the
entering in TX mode transmitting data.
Enter Test: [ESC]#+CMD[CR] to enter in CMD mode
TX Packet: [STX] [DATA] to transmit [DATA]
TX mode
Frame sent by the host on pin RX_DATA is up-converted to RF, modulated and power-amplified.
During TX mode CD# line is shown in Fig. 2 during the TX state.
Active blocks are:
 Transmitter part of transceiver
 Power amplifier
TX Packet Formatting
Transmission starts only sending a data packet with a specific data format and without delay between one
byte to the next one of the data packet. Transmission ends when is transmitted the last byte received from
the host (max 96 bytes). At least transmision ends as soon as sent the 96th byte from the first byte of the
packet.
The [DATA] frame to be transmitted has to be formatted as follows :
The first byte must be [STX] (0x02) : this is the TX key char. As soon as received th STX byte the radio
module start to send a 12 bytes preamble. The preamble is followed from the bytes of the data packet up to
the last one.
The second byte must be the SOF (start of frame byte depending from the protocol used. Now are supported
0xB2 or 0x96 only)
The third byte must be the frame length (from length byte itself to the CRC field excluded).
Follows all other bytes of the packet to be transmitted.
Example:
to transmit the data packet : “0x25 0x10 0x25 0x40 0x11” – 5 bytes,
the packet to be sent to the radio has to be :
[0x02] [0x96] [0x06] [0x25] [0x10] [0x25] [0x40] [0x11] [CRC1] [CRC2].
Number of TX bytes sent =
length (0x06) + 3. [STX], the TX key char, is not sent.
The transmitted preamble is 12 bytes length.