ZTW Mantis G2 ESC telemetry support

[onki69]

ZTW is one of the major ESC manufactureres and many other brands offer these ESCs as OEM solution. https://www.ztwoem.com/product/mantis-g2-85a-105a-125a/ The current Mantis G2 series come with a RX/TX port and using the BT Adapter telemetry values can be read out. Maybe OxS can take advantage of this in order to implament a telemetry feature for this series similar to the Hobbywing Telemetry support. Unfortunately I have no information about the data protocol and my reverse engineering skills are very bad to non existing.

[mstrens]

Without doc about the protocol, it is not possible to implement it.

[onki69]

I got the protocol information from the ESC manufacturer. How can I send it to you?

[mstrens]

I propose that you keep it currently. I try to focus on gyro now.

[onki69]

OK -no problem. Just let me know when you like to take a look at it.

[mstrens]

I hope to be able to look at the doc quite soon. Thanks to provide me the doc for ZTW ESC. I presume you can put it here as a zip file or provide a link to something like google drive

[onki69]

This the info I got:

This data package is used by the ESC for reporting data in real time, and it reports every 50ms. UART Baud 115200 Bps. If the reported voltage is 58.2V, the data will be 0x02, 0x46. Byte0: Packet Header - --- 0xDD Byte1: Protocol No ---- 0x01 Byte2: Data length ----- 0x20 Byte3: Voltage-H
Byte4: Voltage-L (10-1V, data range: 0 0x3e8 100V) Byte5: Current-H Byte6: Current-L (10-1A, data range: 0 0x1388 500A) Byte7: Throttle-PCT (0x01-1%, data range: 0 – 0x64 100% input) Byte8: RPM-H Byte9: RPM-L (0x01-10RPM, data range: 0 – 0xffff ) Byte10: Mos-temp (0x01 – 1℃, data range: 0 –0x96 150℃) Byte11: Motor-temp (0x01 – 1℃, data range: 0 –0x96 150℃) Byte12: Throttle-PWM (0x01-1% , data range: 0 0x64 100% output) Byte13: State-H Byte14: State-L Byte15: Mah-used H high value of the used/consumed power Byte16: Mah-used L low value of the used/consumed power

Byte17: UART-TH serial throttle input Byte18: CAN-TH can throttle Byte19: BEC voltage (0-25V) Byte20- Byte29: reserved Byte30 &31: byte0 byte29 Sum. accumulate & verify State-L explanations for statuses 0x01 Short-circuit protection 0x10 Low-voltage protection 0x02 motor wire break 0x20 Temperature protection 0x04 PPM TH loss protection 0x40 Start locked-rotor 0x08 Power on TH is not zero 0x80 Current protection State-H explanations for statuses 0x01 PPM throttle is not within the regulated range, the PPM throttle is in an abnormal state, and the throttle is not within 700us~2500us.
0x10: the battery voltage is not within the regulated range. 0x02 UART Throttle is not within the regulated range, UART throttle is in an abnormal state, the throttle value exceeds 1000. 0x04 UART throttle loss, UART TH loss
0x08 CAN throttle loss, CAN TH loss

[mstrens]

Thanks for the info. I put 2.9.16 on github (test branch). I hope it support ZTW Mantis ESC. Please note that even if other ESC where already coded in oXs, I think they where not tested. So there could be some more bugs than expected. Let me know if there are bugs. There is a new value for usb command : ESC_TYPE=ZTW1

[onki69]

Wow - that was quick. Testing may take some time as I aam not at home at the moment. I will repond as soon as get some results.

[mstrens]

OK. Always use the latest version in test branch when you start testing. I am also fixing bugs for gyro.

[onki69]

I have connected everthing to a FrSky Archer M+ receiver with FBus. PWM is generated correctly since esc is running the motor on ch3. But the LED is blinking red and no EXC telemetry. her is my config: ` processing cmd

Version = 2.9.26 Function GPIO Change entering XXX=yyy (yyy=255 to disable) Primary channels input = 9 (PRI = 5, 9, 21, 25) Secondary channels input = 255 (SEC = 1, 13, 17, 29) Telemetry . . . . . . . . = 255 (TLM = 0, 1, 2, ..., 29) GPS Rx . . . . . . . . . = 255 (GPS_RX = 0, 1, 2, ..., 29) GPS Tx . . . . . . . . . = 255 (GPS_TX = 0, 1, 2, ..., 29) Sbus OUT . . . . . . . . = 255 (SBUS_OUT= 0, 1, 2, ..., 29) RPM . . . . . . . . . . = 255 (RPM = 0, 1, 2, ..., 29) SDA (I2C sensors) . . . . = 255 (SDA = 2, 6, 10, 14, 18, 22, 26) SCL (I2C sensors) . . . . = 255 (SCL = 3, 7, 11, 15, 19, 23, 27) PWM Channels 1, 2, 3 ,4 = 0 255 2 255 (C1 / C16= 0, 1, 2, ..., 15) PWM Channels 5, 6, 7 ,8 = 255 255 255 255 PWM Channels 9,10,11,12 = 255 255 255 255 PWM Channels 13,14,15,16 = 255 255 255 255 Voltage 1, 2, 3, 4 = 255 255 255 255 (V1 / V4 = 26, 27, 28, 29) RGB led . . . . . . . . . = 16 (RGB = 0, 1, 2, ..., 29) Logger . . . . . . . . . = 255 (LOG = 0, 1, 2, ..., 29) ESC . . . . . . . . . . . = 10 (ESC_PIN= 0, 1, 2, ..., 29)Esc type is ZTW1 (ZTW mantis)

Protocol is Fbus(Frsky) CRSF baudrate = 420000 Logger baudrate = 115200 PWM is generated at = 50 Hz Voltage parameters: Scales : 1.000000 , 1.000000 , 1.000000 , 1.000000 Offsets: 0.000000 , 0.000000 , 0.000000 , 0.000000 No temperature sensors are connected on V3 and V4 RPM multiplier = 1.000000 Baro sensor is not detected Acc/Gyro is not detected Airspeed sensor is not detected No Vspeed compensation channel defined; oXs uses default settings First analog to digital sensor is not detected Second analog to digital sensor is not detected Foreseen GPS type is Ublox (configured by oXs) :GPS is not (yet) detected Led color is normal (not inverted) Failsafe type is HOLD

Gyro is not configured

No sequencers are defined

Config parameters are OK Press ? + Enter to get help about the commands `

[onki69]

I changed to a Jeti receiver but still the LED on the 2040 is blinking red although Telemetry is received in the transmitter and servos outputs are working. I also added a temp sensor on V3. This is the current log output: `Version = 2.9.26 Function GPIO Change entering XXX=yyy (yyy=255 to disable) Primary channels input = 9 (PRI = 5, 9, 21, 25) Secondary channels input = 255 (SEC = 1, 13, 17, 29) Telemetry . . . . . . . . = 255 (TLM = 0, 1, 2, ..., 29) GPS Rx . . . . . . . . . = 255 (GPS_RX = 0, 1, 2, ..., 29) GPS Tx . . . . . . . . . = 255 (GPS_TX = 0, 1, 2, ..., 29) Sbus OUT . . . . . . . . = 255 (SBUS_OUT= 0, 1, 2, ..., 29) RPM . . . . . . . . . . = 255 (RPM = 0, 1, 2, ..., 29) SDA (I2C sensors) . . . . = 255 (SDA = 2, 6, 10, 14, 18, 22, 26) SCL (I2C sensors) . . . . = 255 (SCL = 3, 7, 11, 15, 19, 23, 27) PWM Channels 1, 2, 3 ,4 = 0 1 2 3 (C1 / C16= 0, 1, 2, ..., 15) PWM Channels 5, 6, 7 ,8 = 4 5 6 255 PWM Channels 9,10,11,12 = 255 255 255 255 PWM Channels 13,14,15,16 = 255 255 255 255 Voltage 1, 2, 3, 4 = 255 255 29 255 (V1 / V4 = 26, 27, 28, 29) RGB led . . . . . . . . . = 16 (RGB = 0, 1, 2, ..., 29) Logger . . . . . . . . . = 255 (LOG = 0, 1, 2, ..., 29) ESC . . . . . . . . . . . = 10 (ESC_PIN= 0, 1, 2, ..., 29)Esc type is ZTW1 (ZTW mantis)

Protocol is Jeti (Exbus) CRSF baudrate = 420000 Logger baudrate = 115200 PWM is generated at = 50 Hz Voltage parameters: Scales : 1.000000 , 1.000000 , 3.300000 , 1.000000 Offsets: 0.000000 , 0.000000 , 0.000000 , 0.000000 No temperature sensors are connected on V3 and V4 RPM multiplier = 1.000000 Baro sensor is not detected Acc/Gyro is not detected Airspeed sensor is not detected No Vspeed compensation channel defined; oXs uses default settings First analog to digital sensor is not detected Second analog to digital sensor is not detected Foreseen GPS type is Ublox (configured by oXs) :GPS is not (yet) detected Led color is normal (not inverted) Failsafe type is HOLD

Gyro is not configured

No sequencers are defined

Config parameters are OK Press ? + Enter to get help about the commands 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 8091 A8 F0 8028 64 F0 80E4 F0 8051 F0 80F0 8032 F0 80F0 80F0 80F0 80F0 80F0 80A4 8 F0 80F0 80F0 80A4 F0 80F0 80C4 8A F0 8053 F0 80C9 F0 80D3 12 F0 80F8 80B9 F8 8028 F8 80A8 F8 8009 F6 F0 8069 F5 F0 80F0 8053 F0 8053 F0 80F0 80F0 80F0 80D5 F0 80F0 80F0 8052 29 F5 F0 80E5 F0 8052 9 F0 80F0 8011 F0 80C9 F5 F0 80A9 F0 80A2 12 ED F0 800D F0 80F0 80ED F0 80F0 8035 F0 8085 F0 80F0 80F0 80E8 F0 80E8 5A F0 80C8 6A F0 8020 F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 80F0 `

the 80F0 line onl appears if the motor is not running. The other output is during a motor run. No ESC telemetry visible on the transmitter (only V3 as Temp sensor). By the way, is there a possibiilty to change the name or at least the unit when a temp sensor is connected on the A/D input. I can't change name/unit in the transmitter.

Hope that info is helpful to get the telemetry to work.

[mstrens]

Thanks for the feedback. None of the data match the expected one. When the line begin with 80, it means that it is the first character of a frame (in fact the first char after some delay without char). The doc says that each frame should contains 32 char and so the first one should be "DD" (so here it should be "80DD"). None of the char you got could be a valid frame. That explain why oXs does not provide telemetry.

I would have to make a check on my side in order to generate a valid frame with another computer and see if oXs can get it.

About the temp, I can change the text being displayed and the symbol for the unit. What do you get currently?

[mstrens]

I made some tests. I simulate a frame from ZTW and first oXs did not read the expected values. I made some changes (version 2.10.3) and now oXs get the expected values. Please try this version and post here the data sent by oXs to the USB/serial.

[onki69]

I flshed the 2.10.3 and tested it with the same configuration. The Telemetry fields from the ESC are transmitted to my Jeti transmitter but I get no data from the ESC. Here is a short data dump from the Terminal: `Version = 2.10.3 Function GPIO Change entering XXX=yyy (yyy=255 to disable) Primary channels input = 9 (PRI = 5, 9, 21, 25) Secondary channels input = 255 (SEC = 1, 13, 17, 29) Telemetry . . . . . . . . = 255 (TLM = 0, 1, 2, ..., 29) GPS Rx . . . . . . . . . = 255 (GPS_RX = 0, 1, 2, ..., 29) GPS Tx . . . . . . . . . = 255 (GPS_TX = 0, 1, 2, ..., 29) Sbus OUT . . . . . . . . = 255 (SBUS_OUT= 0, 1, 2, ..., 29) RPM . . . . . . . . . . = 255 (RPM = 0, 1, 2, ..., 29) SDA (I2C sensors) . . . . = 255 (SDA = 2, 6, 10, 14, 18, 22, 26) SCL (I2C sensors) . . . . = 255 (SCL = 3, 7, 11, 15, 19, 23, 27) PWM Channels 1, 2, 3 ,4 = 0 1 2 3 (C1 / C16= 0, 1, 2, ..., 15) PWM Channels 5, 6, 7 ,8 = 4 5 6 255 PWM Channels 9,10,11,12 = 255 255 255 255 PWM Channels 13,14,15,16 = 255 255 255 255 Voltage 1, 2, 3, 4 = 255 255 29 255 (V1 / V4 = 26, 27, 28, 29) RGB led . . . . . . . . . = 16 (RGB = 0, 1, 2, ..., 29) Logger . . . . . . . . . = 255 (LOG = 0, 1, 2, ..., 29) ESC . . . . . . . . . . . = 10 (ESC_PIN= 0, 1, 2, ..., 29)Esc type is ZTW1 (ZTW mantis)

Protocol is Jeti (Exbus) CRSF baudrate = 420000 Logger baudrate = 115200 PWM is generated at = 50 Hz Voltage parameters: Scales : 1.000000 , 1.000000 , 3.300000 , 1.000000 Offsets: 0.000000 , 0.000000 , 0.000000 , 0.000000 No temperature sensors are connected on V3 and V4 RPM multiplier = 1.000000 Baro sensor is not detected Airspeed sensor is not detected No Vspeed compensation channel defined; oXs uses default settings First analog to digital sensor is not detected Second analog to digital sensor is not detected Foreseen GPS type is Ublox (configured by oXs) :GPS is not (yet) detected Led color is normal (not inverted) Failsafe type is HOLD Acc/Gyro is not detected

Gyro is not configured

No sequencers are defined Error in parameters: gyro vertical orientation (0) is not valid

Config parameters are OK Press ? + Enter to get help about the commands 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 8048 50 AC E0 8008 E0 80A4 88 E0 80A4 28 E0 80E0 80E0 8046 AB E0 8023 D1 E0 80E0 80E0 8024 D1 E0 8049 E0 8012 E0 8052 E0 8092 E0 8092 E0 804A A3 E0 8089 F4 E0 8053 E0 8093 E0 80A7 D4 E0 804A E0 80E0 80E0 80E0 8050 E0 80E0 8092 E0 8092 A8 E0 8012 AC E0 80E0 80E0 8050 E0 8050 E0 8050 E0 8027 E0 80E0 80E0 8025 E0 80B2 E0 80A4 12 E0 8054 E0 80E0 8002 E0 8022 E0 8044 24 E0 80C2 E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 80E0 `

Same sequence at the beginning motor is off and I do get the 80E0 Then the motor is started and I do get different data. Motor is stopped and data is same as after start (80E0). Hope this helps.

Regarding the temperature it might be most flexible (if this can be done) to have a kind of "Vx_type" command. By default it is set to "volt" so "Voltage x" is the description and "V" is the unit. When using for instance "v3_type=temp" the description changes to Temp 3 and unit is °C

Best regards and many thanks for your work Onki

[mstrens]

The characters read by oXs are in no way a valid frame. So it is normal that you do not get data on the handset. I do not understand why oXs does not get valid frame while it works on my side when I simulate sending the frame.

Perhaps the issue is linked to the way the ESC output is build at hardware level. Could you try to add a pullup resistor of e.g. 1K between the ESC pin and the 3.3V of the RP2040 and see if you get other characters when the motor runs .

[onki69]

With a3k9 Pullup at the ESC telemetry input it looks like this:

8040 E0 8040 E0 8040 E0 8040 E0 8040 E0 8040 E0 8040 E0 8040 E0 80C4 E0 80E0 80A6 40 E0 80C4 40 E0 80D3 64 40 E0 8013 40 E0 8053 E4 E0 80D3 E0 80E9 F4 40 E0 8040 E0 8040 E0 8040 E0 8040 E0 8040 E0 8040 E0 8040 E0

[mstrens]

This does not match the expected frame at all.

I have no more idea. Could it be that ESC requires some setup to generate telemetry data? Best would be to have a logic analyser to look at the signal but I know you do not have one.

[mstrens]

It seems that there are several projects that use a RP2040 as logic analyser. Here a link to one of them: https://hackaday.com/2022/03/02/need-a-logic-analyzer-use-your-pico/ I never used it because I have a salea clone.

[onki69]

I have done a hex dump using my picoScope software. Probe was connected to the Port 10 with 3k9 pullup. At the beginning the motor was off, then shortly on.

Maybe this helps Dump_motor.csv

[mstrens]

Thanks for the capture. What is the baudrate that you used? Is it 115200? I noticed that the first byte of a frame is DD and the second is 01 as expected in the doc. Still the third one is 00 where the doc says it should be 20. Anyway, even if there is a difference in the third byte, I do yet understand why oXs does not provide the same content for the frames.

[mstrens]

For the capture, did you used a set up : 8bits Even parity 1 stop bit?

[onki69]

For the capture I have used 115200 8N1. Do you need other parameters (8E1)?

[mstrens]

In the doc (some days ago) , it was said that signal was 8E1. So I used this setup in oXs. Still I think that it is not 8E1 but 8N1 because if I calculate the difference between 2 values in the 3rd column, I get (often but not always) a value of 87 (us) which is the delay for 8N1 at 115200. Still, I do not understand why the capture gives some negative values in the 3rd column and the difference is not always 87us. Do you have an explanation?

[onki69]

I can't find the 8E1 setting in my docs. So I have sent another mail to ZTW asking for the confimation about the comm details.

[mstrens]

Sorry, it was not specified if it was 8N1 or 8N1. As kontronik use 8N1, I selected the same option for ZTW. It was a mistake. I put on github a version 2.10.5 where I use 8N1. Can you try this version. I continue to let it display the received char. I hope you will now get the same as with the picolog.

[onki69]

Real-time Data Protocol.docx Sorry about the delay but I was busy this week travelling. Meanwhile I got the info from ZTW that the serial parameters are: 115200 baud, 8 data bits, no Parity, 1 stop bit I need to setup a new 2040 since I grilled mine because of a mechanical accident with a running BLDC. Never use this stuff holding in your hand :-).

I have attached the original doc file I got from ZTW to avoid any transmission error. It was just converted to a docx.

[steffku]

I have a ZTW Skyhawk ESC. Does the current Implementation support this ESC?

[mstrens]

I implemented the ZTW telemetry protocol that is documented in a post here above. Still I am not sure that it has been tested. So there could be some bug. I do not know if the skyhawk model supports this ZTW protocol Best is to make a test.

I can try to fix eventual bugs if I get some feedback.

[steffku]

Hmm, until now i cannot see a sensor on my transmitter when i select discover new sensors. Do i need this resistor between TLM and RX?

[mstrens]

I do not think that you need a resistor. I presume the ZTW protocol has never been totally tested. I first would like to know if oXs get some valid frame from the ESC. I put on github (in test branch) a version 2.13.5 where I print to the PC the characters received from the ESC. Please test it and post here a good sample of the messages (if any). Please note, that a previous test with another user shows that the ESC does not provide valid data when the motor is not running. So you need at least a minimum of power on the motor for the test.

Question: do you have a logic analyser? Some captures could also help to debug the issue.

[steffku]

These are the frames that i get if i give a little bit power on the motor: 80FE FE FE FE FE FE 80FE FE FE FE FE FE 80F8 E6 80F8 80 80F8 86 E0 80F8 FE 80F8 86 F8 80F8 86 80F8 E6 9E 80F8 F8 80F8 E6 80F8 80F8 FE 80F8 E6 80FE FE FE FE FE FE 80FE

I have a Saleae logic analyzer, but don't know how to use it. If you can give me some support here i can have a try.

[mstrens]

The debug messages are not the expected one.

I propose to make a capture with a logic analyser.

Did you already installed the software for the Saleae logic analyser.

Here a link to it: https://www.saleae.com/pages/downloads

Here a link on how to make a capture. https://www.youtube.com/watch?v=XhWKoFj_p9k

To make a capture: first connect the ESC telemetry wire (going to the RP2040) to the logic analyser channel 0. Connect also Grnd from RP2040 (or from ESC, it is the same) to Grnd of logic analyser insert the logic analyser USB cable in PC start the saleae software In the vertical tab on the right side, click on the icon device and select a speed (e.g. 4ms/s) and a duration (e.g. 20 sec). Power the ESC and do not let the motor run. Start a capture with the logic analyser. While the capture is running, change throttle on handset in order to let the motor run (at least at mid power) Let the capture finish. In the salaea software, there is a menu FILE. Select it and then select "Save capture". It will open a popup to save it.

You can then send me this capture e.g. by mail at mstrens@yahoo.fr