Futaba (new) r7008sb sbus problem (with 14SG TX)

[bluuu]

R7008sb is a new RX in FASSTest system.

Futaba make "surprise" and probably changed sbus protocol (and add sbus2).

Together with VIM we make some test. On VIM's working setup new RX can't work.

I done some more test and some reserch on osciloscope.

General information:
- tested sbus output (NOT SBUS2)
- frame time 14ms
- sbus working

See video:


Test circuits and connections:

Connections

Test circuit

Here is few oscilograms:

r7008 12ch mode, w/o inverter

r7008 14ch mode, w/o inverter

r7008 14ch mode, with inverter on cd4049

r7008 14ch mode, with inverter on UCY7404 (oldschool UNITRA (Polish manufacture) ttl neg gate ;) ) my best :)

My microinverter:

My micro inverter

Compare inverted and non inverted signal (microinverter works fine):

compare

I read some aboute this RX and ... other users have similar problems on sbus heli stuff:
http://www.helifreak.com/showthread.php?t=460873

I think Futaba make some changes in sbus protocol. Bill, could you make changes in AQ ? I think the best solution would be add for example "futaba test" radio option.

R7008sb is a new RX but it will be popular. (Futaba add this rx to new 14sg, 14mz and 18mz TX set systems).

[bluuu]

Anybody use r7008sb to test them ?
I'am very angry with that. I bought Futaba for AQ :/
I ordered r6303, comming soon ...

I make video with it. I put it here in hour.

[kinderkram]

Sorry, I can't help - I don't own one nor do I know of anyone using it.

[bluuu]

for more info

http://youtu.be/BsftS-2vmFc

I do the same with inverter, in 12 and 14 channel mode. Still the same result.

I found this library:
http://mbed.org/users/Digixx/code/SBUS- ... l#_details

but I can't use this.

[monkey1]

i have post at 2 months ago about sbus2 cannot work with aq. no one trust me!

[bluuu]

read carefully i write about SBUS, not SBUS2 in this reciver

[monkey1]

R7008SB + t18mz didnt work with AQ (both sbus & sbus2) tested.

My post at 8 Dec
viewtopic.php?f=33&t=1870

[bluuu]

update:

I bought R6303sb - working fine

[JussiH]

Well, gentlemen. I hate to say it, but until Futaba releases data on Sbus and Sbus2 we will just have to wait for someone to retroengineer it using a logic analyzer. Futaba is trying to keep the Sbus and Sbus2 protocols a secret and has frained from making data about the structure available. I assume they must think that is a good idea, but all it does is making it impossible for developers and projects such as this able to implement Sbus and Sbus2.

All current implementations of Sbus, is based on one mans analysis of the protocol, so if he made an error, it will show up all places. Not much we can do about it, and we dont have the luxury of beeing able to buy all TX´s out there to implement the many various protocols into AQ. And we dont have any coders with Sbus or Sbus2 radio gear.

Sooner or later, someone will crack the nut, so Futaba might as well just release the data...but I dont think its gonna happen. They must consider it "top secret" and will only release the data to companies with closed firmwares.

There is of course also the option that a bug has creeped into the source...

[bluuu]

When I get logic analizer I'll try to compare protocols.