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I/O Connector (M9485A)

M9376A and M9377A have the I/O connectors which is used to synchronize the triggering of the analyzer with other equipment. M9376A and M9377A also has the port to generate the pulse for pulse measurement.

IO Port Assignments

The ports on M9376A/M9377A which are assigned to the ports 1 to 4 can be used as the Handler I/O as shown below at the default.

Module	Port name	Signal name	Input/Output	Description
Port 1	I/O1	/READY FOR TRIGGER	Output	Indicates that the instrument is ready for triggering. This signal is changed to the Low level when the instrument is ready for receiving a trigger signal. With the point trigger function on, it goes to the Low level when the instrument is ready to accept the trigger signal for the first point and goes to the High level when the trigger signal for the first point is received. When measurement of all measurement points is completed and the instrument is ready to receive the trigger signal for the first point of the next sweep, this signal goes to the Low level again.
	Trig	/EXTERNAL TRIGGER	Input	An external trigger signal. When the trigger source is set to the "External," this port generates a trigger in respond to the trailing edge of a negative pulse.
	I/O2 (M9376A), I/O2, Sync (M9377A)	/INDEX	Output	Indicates that analog measurement is complete. The /INDEX signal changes to the Low level when analog measurement (all sweeps of all channels) is complete. When the handler receives the signal, it assumes that it is ready to connect the next DUT. However, no measurement data are available until data calculation is completed. When the point trigger function is on, it goes to the High level before staring measurement of the first measurement point and returns to the Low level after completing measurement of all measurement points.
Port 2	I/O1	/SWEEP END	Output	A sweep completion signal. When measurement (all sweeps of all channels) and data calculation are completed, this signal provides a negative pulse.
	Trig	INPUT1	Input	When this port receives a negative pulse, /OUTPUT1 are changed to the Low/High level depending on the setup.
	I/O2 (M9376A), I/O2, Sync (M9377A)	OUTPUT1	Output	Changes to the logic level when /INPUT1 receives a negative pulse. A command can be available for altering the Low/High level logic.
Port 3	I/O1	P1	Output	Hardwired pulse train output #1 (TTL)
	Trig	PULSE SYNC IN	Input	Pulse generator synchronization trigger input (TTL)
	I/O2 (M9376A), I/O2, Sync (M9377A)	P2	Output	Hardwired pulse train output #2 (TTL)
Port 4	I/O1	P3	Output	Hardwired pulse train output #3 (TTL)
	Trig	If the left slot space is not receiver modules, /EXTERNAL TRIGGER	Input	If the left side slot space of port 4 is not receiver modules, this Trig is assigned to an external trigger signal. When the trigger source is set to the "External," this port generates a trigger in respond to the trailing edge of a negative pulse.
	I/O2 (M9376A), I/O2, Sync (M9377A)	P4	Output	Hardwired pulse train output #4 (TTL)
Ports 5 and above	I/O1	N/A	N/A	At default, no signal is assigned to Trig on Ports 5 and above.
	Trig	If the left slot space is not receiver modules, /EXTERNAL TRIGGER	Input	If the left side slot space of port 4 is not receiver modules, this Trig is assigned to an external trigger signal. When the trigger source is set to the "External," this port generates a trigger in respond to the trailing edge of a negative pulse.
	I/O2 (M9376A), I/O2, Sync (M9377A)	Sync	Output	Sync

Modification of Pin Assignments

The user can modify the pin assignments of digital I/O port except for the three signals; READY_FOR_TRIGGER, EXTERNAL_TRIGGER and INDEX which are assigned on the PORT1. If you have two port system, it is necessary to modify this file in order to use the signals of P1 to P4 and PULSE SYNC IN.

Save the definition file according to the following examples. The VNA firmware first initializes the pin assignments to the default condition defined above then read the user defined file.

File name and location to save

C:\\Users\Public\Public Documents\Network Analyzer\m9485a_digitalio.csv

File format

Parameter	Value
<port number>	2 – maximum port number in the 1st chassis
<signal for I/O1>	SWEEP_END, OUTPUT1, P1, P2, P3 or P4, RFOUT_N, NOISE_PORT1 to NOISE_PORT24, NOISE_LO2, AUX1_TRIG_OUT, AUX2_TRIG_OUT
<signal for Trig>	INPUT1 or PULSE_SYNC_IN
<signal for I/O2>	SWEEP_END, OUTPUT1, P1, P2, P3 or P, RFOUT_N, NOISE_PORT1 to NOISE_PORT24, NOISE_LO2, AUX1_TRIG_OUT, AUX2_TRIG_OUT

INPUT1 and OUTPUT1 must be assigned to the same port number

If the same signal is assigned to some of the different I/O ports, the lower port is selected. And if the same signal is assigned to the both of the I/O1 and I/O2 on the same port, the I/O1 is selected.

Auxiliary Trigger

Auxiliary Triggering can be assigned on I/O 1 and 2. See example 7.

I/O signal for Noise Figure measurement

The following signals are available in Noise Figure measurement. This signal can be used to control the external RF switch.

Port name	Signal name	Input/Output	Description
I/O1 or I/O2	/RFOUT_N	Output	Indicates that the source signal is out. This signal is changed to the Low level when the source signal is out.
I/O1 or I/O2	NOISE_PORT1 to NOISE_PORT24	Output	Indicates that noise sweep. This signal is changed to the high level when the target port is used in in a sweep for noise measurement.
I/O1 or I/O2	NOISE_LO2	Output	Indicates that noise sweep for dual-band parallel mode (option). This signal is changed to the high level when the target port is used in in a sweep for dual-band parallel noise measurement.

Example 1

2 ports system with P1, PULSE SYNC IN, P2

(SWEEP_END, INPUT1, OUTPUT1, P3 and P4 are not used)

	PORT1	PORT2
I/O 1	READY FOR TRIGGER	P1
Trig	EXTERNAL TRIGGER	PULSE SYNC IN
I/O 2 (M9376A), I/O2, Sync (M9377A)	INDEX	P2

File format example

2, P1,PULSE_SYNC_IN,P2

Example 2

2 ports system with SWEEP_END, PULSE SYNC IN, P1

( INPUT1, OUTPUT1, P2 to P4 are not used)

	PORT1	PORT2
I/O 1	READY FOR TRIGGER	SWEEP_END
Trig	EXTERNAL TRIGGER	PULSE SYNC IN
I/O 2 (M9376A), I/O2, Sync (M9377A)	INDEX	P1

File format example

2, SWEEP_END,PULSE_SYNC_IN,P1

Example 3

4 ports system, signal locations are assigned differently from default as shown below.

	PORT1	PORT2	PORT3	PORT4
I/O 1	READY FOR TRIGGER	SWEEP_END	OUTPUT1	P4
Trig	EXTERNAL TRIGGER	N/A	INPUT1	PULSE SYNC IN
I/O 2 (M9376A), I/O2, Sync (M9377A)	INDEX	P1	P2	P3

File format example

2, SWEEP_END,,P1

3, OUTPUT1,INPUT1,P2

4, P4,PULSE SYNC IN,P3

Example 4

6 ports system for Noise Figure measurement, signal locations are assigned differently from default as shown below.

	PORT1	PORT2	PORT3	PORT4	PORT5	PORT6
I/O 1	READY FOR TRIGGER	RFOUT_N	NOISE_PORT3	NOISE_PORT4	NOISE_PORT5	NOISE_PORT6
Trig	EXTERNAL TRIGGER	N/A	N/A	N/A	N/A	N/A
I/O 2 (M9376A), I/O2, Sync (M9377A)	INDEX	N/A	N/A	N/A	N/A	N/A

File format example

2, RFOUT_N, ,

3, NOISE_PORT3, ,

4, NOISE_PORT4, ,

5, NOISE_PORT5, ,

6, NOISE_PORT6, ,

Example 5

M9376A/77A 4 ports system with one M9379A RF Amplifier between ports 2 and 3. The I/O2 on Port 2 and Trig on Port 3 should be connected with SMB cable.

	PORT1	PORT2		PORT3	PORT4
Module	M9376A	M9377A	M9379A	M9377A	M9377A	M9379A
I/O 1	READY FOR TRIGGER	SWEEP END		P1	P3
Trig	EXTERNAL TRIGGER	PULSE SYNC IN		EXTERNAL TRIGGER	N/A
I/O 2 (M9376A), I/O2, Sync (M9377A)	INDEX	SYNC		P2	N/A

File format example

2, SWEEP_END,,PULSE_SYNC_IN,

3, P1, ,P2

4, P3, ,

Example 6

M9376A 4 ports system with one M9379A between ports 2 and 3. The Sync on Port 2 and Trig on Port 3 should be connected with SMB cable.

	PORT1	PORT2		PORT3	PORT4
Module	M9376A	M9376A	M9379A	M9376A	MM9376A	M9379A
I/O 1	READY FOR TRIGGER	SWEEP END		P1	P3
Trig	EXTERNAL TRIGGER	PULSE SYNC IN		EXTERNAL TRIGGER	EXTERNAL TRIGGER
Sync	N/A	Sync ON		N/A	N/A
I/O 2 (M9376A), I/O2, Sync (M9377A)	INDEX	N/A		P2	N/A

File format example

2, SWEEP_END,,PULSE_SYNC_IN,

3, P1, ,P2

4, P3, ,

Example 7

4 ports system, assign Auxiliary Triggering for I/O 2 on ports 2 and 4.

	PORT1	PORT2	PORT3	PORT4
I/O 1	READY FOR TRIGGER	SWEEP_END	P1	P3
Trig	EXTERNAL TRIGGER	N/A	PULSE SYNC IN	N/A
I/O 2 (M9376A), I/O2, Sync (M9377A)	INDEX	AUX1_TRIG_OUT	P2	AUX2_TRIG_OUT

File format example

2, SWEEP_END,,AUX1_TRIG_OUT

3, P1,PULSE SYNC IN,P2

4, P3,,AUX2_TRIG_OUT

Restriction of the usage of M9377A I/O2

In case of the multi-chassis configuration and M9377A is used as the 1st port receiver, the I/O2 pin must be used as Sync pin to synchronize over the chassis. Then the INDEX signal cannot be output from the I/O2 of PORT1. In this special case the INDEX signal is output from the I/O1 pin of the 1st port receiver in the 2nd chassis.

Restriction of the P1 to P4 and PULSE SYNC IN

In case of the multi-chassis configuration, the P1 to P4 can be assigned to the receivers installed in the 1st chassis. The PULSE SYNC IN can be assigned to the receivers installed in the slots which belong to the same trigger bus segment of the 1st port receiver. In standard configuration, both receiver should be in slots No. 7 to 12 for M9018A. Refer to M9018A users guide for the trigger bus segment.

Pin Descriptions

Input1 When this Input line receives a Low pulse from the material handler, data is latched on the OUTPUT1 lines.
The Input Line activity can be read:
SCPI
CONTrol:HANDler:INPut?

Output1 The current state of these latched TTL outputs may be set High or Low (Default setting) using the (non-user) OUTPUT commands. The next state (following a negative edge on the INPUT1 line) may be pre-loaded to High or Low (Default setting) using the user commands. For example, on the next negative pulse on the INPUT1 line, you want the OUTPUT1 line to go from 0 to 1. To do this: CONT:HAND:OUTP1:DATA 0 'Force the OUTPUT1 line to 0 CONT:HAND:OUTP1:USER 1 'Set the OUTPUT1:USER buffer to 1, indicating the next state
	SCPI
Write User Data	CONT:HAND:OUTP1:USER
Read last value written	CONT:HAND:OUTP1:USER
Write non-user data	CONT:HAND:OUTP1:DATA
Read last value written	CONT:HAND:OUTP1:DATA

External Trigger

When trigger source is set to external, this Input line accepts a trigger signal from the material handler. This usually means that a part is in place and ready to be tested.

Sweep End This output line indicates the status of the VNA sweep. The sweep includes sweeping the source and taking data. Low (falling edge) indicates that the specified sweep event has finished. This does NOT indicate that all calculations have finished. High indicates that the specified sweep event is active.
Set Sweep Event Mode: Sweep: indicates that a single source sweep has finished. (Default setting) Channel: indicates that a single channel has finished. Global: indicates that all enabled channels have finished.
SCPI
CONTrol:HANDler:SWEepend

Timing Diagrams

	Description	Minimum	Typical
T1	Pulse width of /EXTERNAL TRIGGER	0.1 µs
T2	Pulse width of /SWEEP END		10 µs

	Description	Minimum	Typical
T1	Pulse width of /INPUT1	0.1 µs
T2	Response time of /OUTPUT1		0.1 µs

Last modified:

17-3636-2024

New topic

I/O Connector (M9485A)

IO Port Assignments

Modification of Pin Assignments

File name and location to save

File format

Auxiliary Trigger

I/O signal for Noise Figure measurement

Example 1

File format example

Example 2

File format example

Example 3

File format example

Example 4

File format example

Example 5

File format example

Example 6

File format example

Example 7

File format example

Restriction of the usage of M9377A I/O2

Pin Descriptions

Input1

Output1

External Trigger

Sweep End

Timing Diagrams