FSUIPC Offsets for Motorized Throttle control with PMDG 737

[chanakaf]

*** Moved from User Contributions sub-forum to main support forum ***

Hello All,

I am trying to figure out which offsets to use to motorize my 737 TQ. I want to use these offsets to write a simple LUA script and send data to a serial port and then control the TQ via Arduino.

I am running P3D V4, PMDG 737 with FSUIPC V6

I could use 088C and 0924 to get the Throttle Lever position.

Which offsets should I use to get the 'Commanded Throttle Position' within AP? should I use 07F8 (AP_RPM_N1_Value) or 0730(Target_speed_for_throttle_feedback) and then check the difference between them?

Any help on how to formulate this equation would be much appreciated.

I have been trying to do this for some time now and had some previous posts on this topic, but have not been able to fully resolve. Getting close though.

Thank You!

Anthony

Edited July 10, 2023 by John Dowson
Moved to main support forum

[John Dowson]

7 hours ago, chanakaf said:

I could use 088C and 0924 to get the Throttle Lever position.

Wouldn't offsets 0x3330 and 0x3332 be better? 0r 0x089A and 0x0932?

7 hours ago, chanakaf said:

Which offsets should I use to get the 'Commanded Throttle Position' within AP? should I use 07F8 (AP_RPM_N1_Value) or 0730(Target_speed_for_throttle_feedback) and then check the difference between them?

I am not sure about this - best to just monitor the offset values using FSUIPC's offset monitoring facilities, to see how they change when the AP has control. May also be worth looking at offsets 0x0898 and 0x0930.

I have moved your post to the correct support forum - hopefully some other motorized TQ users will see this and can help you...

John

[chanakaf]

Thanks John. I have tried the additional offsets you suggested and don't quite see anything different. In further reading and understanding offsets, I agree using 0x3330 and 0x3332 is better. I was not able to get any values from 0x089A and 0x0932 for some reason.

When AT is not engaged I can see the throttle axis values and also the Engine N1 values.

When AT is Engaged, I am trying to find a value for the commanded position of the throttle for each engine so I can calculate the error between the physical lever posion and the desired position based on commanded engine speed.

Anyone has any ideas on suitable offsets to use for a motorized throttle control?

Thanks.

[John Dowson]

On 7/10/2023 at 3:22 AM, chanakaf said:

should I use 07F8 (AP_RPM_N1_Value)

Shouldn't this be 0x07FA (Autopilot RPM (N1) hold value, 16384 = 100% N1) - did you try that one?

11 hours ago, chanakaf said:

When AT is not engaged I can see the throttle axis values and also the Engine N1 values.

Don't the same offsets also show the throttle axis value and engine N1 values when AT is engaged?

[chanakaf]

Thanks John. For some reason, I can't get any values for 0x07FA, I cant find this in the offset in the FS interrogate tool either.

From looking at all the data streams, I think I can do what I need to do by calculating the difference between 0x088C and 0x3330 for Throttle 1 when AT is engaged (0x0810).

I appreciate your help.

[John Dowson]

Ok. Unfortunately I don't have the PMDG 737 for P3D, so cannot check the offsets here. I can see if Pete has a copy and he can maybe check, but that won't be until later next week now as he is on holiday.

Let me know how you get on.

Regards,

John