Newland NLS-EM1395, Руководство по интеграции

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13
Communication Protocol
The following describes how the host sends a command to the EM1395.
Step 1: The host lowers the CTS (to request to send), then checks the state of the RTS.
Step 2: When the engine detects the CTS is low, it lowers the RTS (to grant permission).
Step 3: When the host detects the RTS is low, it asserts the CTS (to remove request), then check the state
of the RTS.
Step 4: When the engine detects the CTS is high, it asserts the RTS (to remove permission).
Step 5: When the host detects the RTS is high, it sends command to the RXD pin.
Step 6: The engine processes the command received, then sends a response to the TXD pin to
ackowledge receipt when necessary.
If the host wants to send another command, repeat the steps above.