PDA

View Full Version : DSMx vs DSM2


jperkosk
03-27-2011, 09:54 AM
Did some simple experiments on DX8 and AR8000 pair to check DSM2 compatibility of DSMx enabled equipment, and it looks 100% compatible, as claimed, meaning DSMx has a full DSM2 functionality build into it.

When AR8000 is bound to DX8 in DSM2 mode, I can cycle the Rx power and the familiar brownout alarm comes on. This is because DSM2 Rx stores in the flash memory the two channels that the Tx has last selected. When powering up, the Rx checks if the Tx is operating on the same 2 channels as last time. If not, everything is OK and the new channels get stored in the flash memory. If yes, the Rx concludes that it has gone through a brownout and it activates the flashing brownout indicator.

Since DSMx implements channel hopping (it selects 23 channels out of available spectrum, based on Tx GUI), there is no last 2 channel memory, so in DSMx mode the brownout indicator is gone; I have cycled the Rx power to confirm it, and logically, no brownout indicator appeared.

UPGl2AYDD
03-28-2011, 12:55 AM
Good to hear it's all backwards compatible for sure. I had my thoughts there would be "missing" things.

Rob2160
07-30-2011, 07:53 PM
Did some simple experiments on DX8 and AR8000 pair to check DSM2 compatibility of DSMx enabled equipment, and it looks 100% compatible, as claimed, meaning DSMx has a full DSM2 functionality build into it.

When AR8000 is bound to DX8 in DSM2 mode, I can cycle the Rx power and the familiar brownout alarm comes on. This is because DSM2 Rx stores in the flash memory the two channels that the Tx has last selected. When powering up, the Rx checks if the Tx is operating on the same 2 channels as last time. If not, everything is OK and the new channels get stored in the flash memory. If yes, the Rx concludes that it has gone through a brownout and it activates the flashing brownout indicator.

Since DSMx implements channel hopping (it selects 23 channels out of available spectrum, based on Tx GUI), there is no last 2 channel memory, so in DSMx mode the brownout indicator is gone; I have cycled the Rx power to confirm it, and logically, no brownout indicator appeared.

Yes, thanks for this post..

I just made a video confirming what you have said.. Its easy with the DX8 which shows the mode you are in, but for other JR and the Spektrum DX6i radio, the brownout flash or lack thereof is the only real way to confirm DSM2 vx DSMX mode..

Vid here..

http://www.youtube.com/watch?v=4_Tbes9f1_c

jperkosk
07-30-2011, 08:12 PM
Using a mode 1 on your DX6i and having a plank selected I'm not sure your demo vid can be fully trusted...
(just kidding)
Great demo to illustrate this effect, Rob!