
2 - 32 MP6000 BAR CODE PROGRAMMING GUIDE
Hardware Handshaking
The data interface consists of an RS-232 port designed to operate either with or without the hardware
handshaking lines, Request to Send (RTS), and Clear to Send (CTS).
Disable Standard RTS/CTS handshaking to transmit scan data as it becomes available. Select Standard
RTS/CTS handshaking to transmit scan data according to the following sequence:
•
The MP6000 reads the CTS line for activity. If CTS is asserted, the scanner waits up to Host Serial
Response Timeout for the host to de-assert the CTS line. If, after Host Serial Response Timeout
(default), the CTS line is still asserted, the scanner sounds a transmit error, and discards any scanned
data.
•
When the CTS line is de-asserted, the MP6000 asserts the RTS line and waits up to Host Serial
Response Timeout for the host to assert CTS. When the host asserts CTS, the scanner transmits data.
If, after Host Serial Response Timeout (default), the CTS line is not asserted, the scanner sounds a
transmit error, and discards the data.
•
When data transmission completes, the MP6000 de-asserts RTS 10 msec after sending the last
character.
•
The host should respond by negating CTS. The MP6000 checks for a de-asserted CTS upon the next
transmission of data.
During the transmission of data, the CTS line should be asserted. If CTS is de-asserted for more than 50 ms
between characters, the MP6000 aborts transmission, sounds a transmission error, and discards the data.
If this communication sequence fails, the MP6000 issues an error indication. In this case, the data is lost and
must be re-scanned.
If hardware handshaking and software handshaking are both enabled, hardware handshaking takes
precedence.
NOTE The DTR signal is jumpered to the active state.
Komentarze do niniejszej Instrukcji