Taranis with DX4 hack module: DSM2 Rec binds in DSMX mode?

[pmullen503]

I was programming my Taranis (R-2940 firmware) with a Spectrum hack module from a DX4 and ran into a strange result. I was programming in an older model with a LemonRx DSM2 receiver. The receiver would only bind when the Taranis was set to DSM2=>DSMX protocol (Not DSM2=> DSM2). Internal module is off, hack module is the external bay.

The model range tested and flew fine but why wouldn't it bind as DSM2=>DSM2 mode as I would expect? Note that everything was programmed in the TX not with C9x at all.

The only other spektrum receiver bound to the module is a DSMX rec. and that I bound in DSM2=>DSMX mode. It will not bind in the DSM2=>DSM2 mode either.

Is this an issue with the firmware or the DX4 module?

[Daedalus66]

Take a look at the Lemon thread over on RCG for a discussion of the 11ms vs 22ms issue, which might have something to do with this one. The Lemon spokesperson is an active participant there. This doesn't answer your question but might help understand what's going on.

[pmullen503]

This is an older 6ch DSM2 receiver, one of the first released. It's possible the module needs to be forced into the right mode but I would have expected DSM2=>DSM2 rather than DSM2=>DSMX.

Anyway, I rebound several models with OrangeRX, genuine Spektrum, and LemonRx receivers with the same module in my 9x and then in the Taranis. Everything acted as it should except this particular combination of LemonRX rec. and the module in the Taranis. What's weird is that the 9x has a internal HP6DSM module (definitely DSM2 only, DPDT switch selects internal or module bay) and that binds just fine with the same LemonRx rec. in DSM2=>DSM2 only mode. The external module (made from a DSMX capable DX4 tx) binds in DSM2=>DSM2 only mode in the 9x but requires DSM2=>DSMX mode to bind with the Taranis.

The firmware for Taranis may handle things differently than ER9x (or Opentx for the 9x).

There aren't lots of reports of hack module DSM2/X issues with the Taranis firmware so I'm not really worried, but I thought I'd report the issue with the 6ch DSM2 LemonRx receiver in case someone else runs into the same problem.

[Daedalus66]

I'm about to set up an external module with DX4e unit. Will report on any anomalies.

I have always wondered whether the modules from the early DX4e transmitters pose a problem. You will remember that they were recalled because they didn't work properly with some of the 6-channel DSM2 receivers, such as the AR6100.

There was also a change along the way that made it possible to change stick mode in software and to turn on expo. Neither of these features worked with the early DX4e, but I assume they are a function of the main board, not the module, so don't matter.

[NI0X]

Just a quick question I didn't find an answer to:
If I take a module form a DX4, will it transmit 8 channels?

[Kilrah]

No, it only supports 6.

[NI0X]

Is it limited by the Taranis or by the module itself?

[jhsa]

The module itself..

[NI0X]

And a dx5 module? I think it's 6 channels too?

[Kilrah]

The DX4-5-6i use the same module, and it supports only 6 channels. Others use a different module that can't be used with this mod.

[NI0X]

Thank you for this information