User manual

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4.1.2 USB (Virtual COM) Settings
The USB (virtual COM) interface settings for the communication port are as follows:
BAUDRATE: 115200
PARITY: NONE
DATA BITS: 8
STOP BIT: 1
FLOW CONTROL: NONE
4.2 Device States
The device may be in one of the two possible states described below.
4.2.1 Local State (LOCS)
In the LOCS state, the device may be operated from the front panel.
4.2.2 Remote State (REMS)
In the REMS state, the device may be operated from the USB interface. Actuating any front
panel key will cause the device state to revert to the LOCS.
4.3 Message Exchange Protocol
The device decodes messages using the Message Exchange Protocol similar to the one
defined in IEEE 488.2. The following functions implemented in the MEP must be considered:
4.3.1 The Input Buffer
The device has a 128-byte long cyclic input buffer. Decoding of remote messages is begun as
soon as the input buffer is not empty, that is, as soon as the controller has sent at least one
byte to the device. Should the input buffer be filled up by the controller faster than the device
can remove the bytes and decode them, the bus handshake (CTS/RTS) is used to pause data
transfer until room has been made for more bytes in the buffer. This prevents the controller
from overrunning the device with data.
4.3.2 The Output Queue
The device has a 100-byte long output queue in which it stores response messages for the
controller to read. If at the time a response message is formatted the queue contains
previously formatted response messages, such that there is not enough places in the queue