lux v2 FC; will it work on a tri-copter

[irekkin]

a couple of months ago I was here asking about this board and how to wire it up for a tri-copter. I ended up going with an RCexplorer f3fc, which worked out really well. I busted up my other tri pretty bad the other day and since I've got to do some major repairs I'd like to replace the naze 32 with the lux V2. my main question is will the lux board even work on a tri-copter. the product description page has a disclaimer that states " Please note: PWM input for individual channels is not supported. ". what exactly does that mean? on the few boards I have experience with you usually have 6-8 motor/pwm slots and one of them can usually be assigned to the servo. looking at the resource and resource list in the cli the lux only has 4 motor slots no matter what configuration ( tri, quad, octo, etc. ) everything else is serial rx/tx. I'm going to try the #4 motor slot but I have a feeling it's not going to work. any thoughts will be most appreciated

 

[LitterBug]

Sure it will work. You can run TriFlight on it. You will need a single output serial receiver rather than an RX with individual channel outputs. You may have to remap the servo to the correct output. I have one of these boards that I've never used. I could through TriFlight on it and look at the mapping to see what the default pinouts are, or even come up with the correct resource mapping to match what you have.

Cheers!
LitterBug

 

[irekkin]

thanks for the help LB. I understand what the disclaimer means now. running an s-bus receiver is no problem, in fact this tri is running an x4r-sb. I've got the latest version of tri-flight on the lux board now. here's the resource and resource list from the cli.

CLI

# resource
resource BEEPER 1 B09
resource MOTOR 1 C06
resource MOTOR 2 C07
resource MOTOR 3 C08
resource MOTOR 4 C09
resource PPM 1 A08
resource LED_STRIP 1 A06
resource SERIAL_TX 1 C04
resource SERIAL_TX 2 A14
resource SERIAL_TX 3 B10
resource SERIAL_RX 1 C05
resource SERIAL_RX 2 A15
resource SERIAL_RX 3 B11

# resource list
IO
A00: FREE
A01: FREE
A02: FREE
A03: FREE
A04: MPU_CS
A05: MPU_EXTI
A06: FREE
A07: FREE
A08: FREE
A09: FREE
A10: FREE
A11: FREE
A12: FREE
A13: FREE
A14: FREE
A15: SERIAL_RX 2
B00: FREE
B01: FREE
B02: FREE
B03: SPI_SCK 1
B04: SPI_MISO 1
B05: SPI_MOSI 1
B06: FREE
B07: FREE
B08: FREE
B09: BEEPER
B10: FREE
B11: FREE
B12: SDCARD_CS
B13: SPI_SCK 2
B14: SPI_MISO 2
B15: SPI_MOSI 2
C00: ADC_BATT
C01: FREE
C02: FREE
C03: ADC_RSSI
C04: FREE
C05: FREE
C06: MOTOR 1
C07: MOTOR 2
C08: MOTOR 3
C09: FREE
C10: FREE
C11: FREE
C12: FREE
C13: SDCARD_DETECT
C14: LED 2
C15: LED 1
D02: FREE
F00: FREE
F01: FREE
F04: FREE


DMA:
DMA1 Channel 1: ADC
DMA1 Channel 2: FREE
DMA1 Channel 3: FREE
DMA1 Channel 4: FREE
DMA1 Channel 5: SDCARD
DMA1 Channel 6: FREE
DMA1 Channel 7: FREE
DMA2 Channel 1: FREE
DMA2 Channel 2: FREE
DMA2 Channel 3: FREE
DMA2 Channel 4: FREE
DMA2 Channel 5: FREE

this is what I was going to try, let me know what you think

resource motor 4 none
resource servo 1 C09

my other thought was to use one of the serial Rx pins (1 or 3 ), but I did'nt know if you could do that.

 

[LitterBug]

Servo mapping should be a matter of doing the following three commands:

Resource motor 4 none
Resource servo 1 c09
save

That frees up C09 from the motor on pwm 4 and maps the servo to pwm 4

Note that even though you map servo 1, servo 5 is the logical servo that is used

CLI

# diff
# Triflight 0.7 Beta 2 / LUXV2_RACE 3.1.7 Jun  4 2017 / 13:34:07 (1698ba5)
resource MOTOR 4 NONE
resource SERVO 1 C09
servo 5 1000 2000 1500 40 40 100 -1

Cheers!
LitterBug

 

[irekkin]

thanks again. hope to get it up and going again this weekend. if I do maybe i'll post a short video. I'm trying to teach myself how to do flips and rolls so it ought to be good for a few laughs.

 

[irekkin]

just for future reference. after much soldering and re-soldering, cussing and head scratching I contacted RCexplorer on their support page and this is their reply.







RCExplorer <support@rcexplorer.se>


4:21 AM (6 hours ago)








to me











----------reply above----------


RCExplorer - David (admin@rcexplorer.se) wrote:
Hi Randy.
Triflight has all the same targets as Betaflight as it's just a modified version of betaflight with the tricopter features added. The code can be run on all those boards but the problem is that some boards are not designed with servos in mind. The problem is that the manufacturer has selected pins on the processor that uses the wrong timers for working as a servo output. Even if you remap one of the ESC pins to be a servo output it simply can't output the required signal. The LUX only has those 4 PWM ESC output pins and no spare ones that might have worked. It also uses the UART as a PPM input which means it doesn't even have the PPM pin to use as an output.
You might be able to get the servo output working by stealing a UART or LED pin but that requires breaking down the firmware and recompiling it as it can't be done via CLI.

Sorry for the bad news
/David

live and learn

 

[LitterBug]

Hmmmm.

LB