Agilent Technologies E4406A VSA manual Character Format Parameters, Modem Line Handshaking

Programming Fundamentals

Overview of the RS-232 Bus

Character Format Parameters

To define the character format, you must know the requirements of the peripheral device for the following parameters:

•Character Length: Eight data bits are used for each character, excluding start, stop, and parity bits.

•Parity Enable: Parity is disabled (absent) for each character.

•Stop Bits: One stop bit is included with each character.

Modem Line Handshaking

To use modem line handshaking for data transfer you would consider the following tasks:

1.Set Data Terminal Ready and Request-to-Send modem lines to active state.

2.Check Data Set Ready and Clear-to-Send modem lines to be sure they are active.

3.Send information to the interface and thence to the peripheral.

4.After data transfer is complete, clear Data Terminal Ready and Request-to-Send signals.

For ENTER operations:

1.Set Data Terminal Ready line to active state. Leave Request-to-Send inactive.

2.Check Data Set Ready and Data Carrier Detect modem lines to be sure they are active.

3.Input information from the interface as it is received from the peripheral.

4.After the input operation is complete, clear the Data Terminal Ready signal.

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