Mindeo FS580, User Manual

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5
Serial Communication Interface
Note: SCI is supported for RS232 interface or USB virtual COM only.
This section describes the system requirements of the Serial Communication Interface (SCI), which
provides a communication link between a scanner and a host via RS232 interface or USB virtual COM.
SCI allows the host to configure the scanner. All communication between the scanner and the host occur
over the hardware interface lines using the SCI protocol.
The host and the scanner exchange messages in packets. A packet is a collection of bytes framed by
the proper SCI protocol formatting bytes. The maximum number of bytes per packet allowed by the SCI
protocol for any transaction is 257 (255 bytes of data + 2 bytes of checksum).
Decode data may be sent as ASCII data (unpacked), or as part of a larger message (packeted),
depending on the scanner configuration.
Table 5-1 SCI commands
No. Command name Operation code Description
1 BEEP 0x42(‘B’) Sound the beeper.
2 CMD_ACK 0x59(‘Y’) Positive acknowledgement.
3 CMD_NAK 0x4E(‘N’) Negative acknowledgement.
4 DECODE_DATA 0x50(‘P’) Decode data in SCI packet format.
5 LED_CTR 0x4C(‘L’) Turn on/off the led.
6 REQUEST_REVISION 0x56(‘V’) Request scanner’s software revision.
7 REPLY_REVISION 0x52(‘R’) Reply scanner’s software revision.
8 START_DECODE 0x53(‘S’) Tell scanner to attempt to decode a barcode.
9 STOP_DECODE 0x45(‘E’) Tell scanner to abort a decode attempt.
10 PARAM_DEFAULT 0x25(‘%’) Load scanner’s default settings.
11 PARAM_REQUEST 0x3F(‘?’) Request values of certain parameters.
12 PARAM_SEND 0x23(‘#’) Parameter transmission.
13
CUSTOM_DEFAULTS 0x26(‘&’) Custom defaults option to write/restore.
14
CMD_RESTART 0x5e(‘^’) Tell scanner to restart as soon as possible.
15
WAKUP N/A Wakeup scanner after it has been in sleep state.
16 CMD_OUTPUTBUFFER_CTR 0x62(‘b’) Control output buffer.