Spellman uX SERIES, Инструкция по эксплуатации

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118153-001 Rev. B
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uX_Manual.doc REV -
7.0 Command Handling
7.1 Command Time Out
The host computer should set a serial time out at approximately 100mS. This
allows the MCU to process the incoming message, and transmit a response. The
MCU will typically initiate a reply to incoming messages in approximately 1-2mS,
with a worst case of 5mS.
7.2 Buffer Flushing
The MCU will flush the incoming serial data buffer every time an STX is received.
This provides a mechanism to clear the receive buffer of partial or corrupt
messages.
7.3 Handshaking
The only handshaking implemented on the host interface, is built in to the
implementation of this protocol. That is, the host must initiate all communications.
If the supply receives a program command, an acknowledge message is sent
back to the host via the “$” message. If the host does not receive an
acknowledge within the time out window, the host should consider the message
lost or the device off-line.
Similarly, if the supply receives a request command, the requested data is sent
back to the host. If the host does not receive the requested data within the time
out window, the host should consider the message lost or the device off-line.
This essentially uses the full-duplex channel in a half-duplex communication
mode.