Intermec Sabre 1555, Руководство программиста

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Sabre 1555 RFID & Bar Code Reader Programmer’s Reference Manual
4-20
For example, in the ESA command, the host requests communication at 57600 bauds.
The product is limited to 19200 bauds and its current speed is 9600 bps, so
synchronization occurs at 9600 bauds. As the ASI response returned by the product
indicates that it cannot communicate at a baud rate higher than 19200, host and
product then switch to 19200 bauds
The syntax without STX and ETX is as follows:
<ESA><HPR><BRR><FM><CHK>
<ESA> External Synchronization Attempt (0x04)
<HPR> Hardware Protocol Requested [0 - 2]
0 = not used;
1 = Host CTS/RTS;
2 = Product CTS/RTS
<BRR> Baud Rate Requested
[0 - 12] = [75, 150, 300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200,
230400]
<FM> Frame Marker
bit M = 0;
bit ACK = 0;
bit reset = 1;
frame number = 0
The response is as follows:
<ACK> character
<ASI> <ESA> <HPC> <BRC> <CFG> <FM> <CHK>
<ASI> Accepted PPP Command and Sending Information (0x03)
<ESA> External Synchronization Attempt (0x04)
<HPC> Hardware Protocol Confirm
[0 - 2]
0 = not used;
1 = Host CTS/RTS;
2 = Product CTS/RTS
<BRC> Baud Rate Confirm
[0 - 12] = [75, 150, 300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200,
230400]
<CFG> Configuration
b0 = setup parameters in NVM;
b1 = remote communication without beep;
b3, b2 reserved;
b7 - b4 must be set to 0.
<FM> Frame Marker
Once synchronization has been achieved with the product using ESA command, it is
necessary for the host to change communications parameters to the following:
"Baud_Rate_Requested (BRR), 8, N, 2". In other words, although the baud rate is
specified in the ESA command as a parameter, the number of data bits, parity and stop bits