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SHC Connection to OnSTEP STM32

helmutliebenau@...
 

Hello erveryone,

I am looking for my problem with the connection SHC to OnStep STM32 Blue Pill.

The Status is:
OnStep works fine with the App and Sky Planetarium.
In config.STM32.h the SHC are following defined: #define ST4_PULLUP and #define ST4_HAND_CONTROL_ON.
The pullup resistor on Onstep and on SHC are mounted.

If the ST4 cabel is connected the SHC display shows after a few seconds: "connection failed"
Also when only the USB cabel is connected on the teensy 3.2.
I also tried two different ST4 cabel. But without success.

Maybe the problem is the display? The pins are VDD, GND, SCK, SDA. The order of pin (GND,VCC) are differnt between the SHC PCB and the display.
So I did make sure that GND and VCC are right connected with SHC PCB and the display.
But maybe the problem is the pin SCK? On the PCB this pin namend SCL.

Thanks for your support!


Dave Schwartz
 

If you are getting the 'connection failed' message on the display then the pins are wired correctly.

Be sure that the cable you are using for an ST4 cable is correct. A real ST4 cable is wired straight-through... many that are for telephone use have some crossover wiring. An ST4 cable looks like this image - note that the wire colors are in the same order left-to-right.

On 2020-01-12 12:17 p.m., helmutliebenau@... wrote:
Hello erveryone,

I am looking for my problem with the connection SHC to OnStep STM32 Blue Pill.

The Status is:
OnStep works fine with the App and Sky Planetarium.
In config.STM32.h the SHC are following defined: #define ST4_PULLUP and #define ST4_HAND_CONTROL_ON.
The pullup resistor on Onstep and on SHC are mounted.

If the ST4 cabel is connected the SHC display shows after a few seconds: "connection failed"
Also when only the USB cabel is connected on the teensy 3.2.
I also tried two different ST4 cabel. But without success.

Maybe the problem is the display? The pins are VDD, GND, SCK, SDA. The order of pin (GND,VCC) are differnt between the SHC PCB and the display.
So I did make sure that GND and VCC are right connected with SHC PCB and the display.
But maybe the problem is the pin *SCK*? On the PCB this pin namend SCL.

Thanks for your support!


Dave Schwartz
 

that may not be totally relevant... I just twigged to the fact that you mentioned you are using a Teensy SHC which does not have an RJ connector for the cable.

Regardless, ensure your cable is wired correctly... wire 1 is the 5V, wire 2 is GND and the other 4 signal lines must be in the correct order because the controller and SHC exchange specific signals over them in order for the SHC to be recognized.

On 2020-01-12 12:34 p.m., Dave Schwartz wrote:
If you are getting the 'connection failed' message on the display then the pins are wired correctly.

Be sure that the cable you are using for an ST4 cable is correct. A real ST4 cable is wired straight-through... many that are for telephone use have some crossover wiring. An ST4 cable looks like this image - note that the wire colors are in the same order left-to-right.

On 2020-01-12 12:17 p.m., helmutliebenau@... wrote:
Hello erveryone,

I am looking for my problem with the connection SHC to OnStep STM32 Blue Pill.

The Status is:
OnStep works fine with the App and Sky Planetarium.
In config.STM32.h the SHC are following defined: #define ST4_PULLUP and #define ST4_HAND_CONTROL_ON.
The pullup resistor on Onstep and on SHC are mounted.

If the ST4 cabel is connected the SHC display shows after a few seconds: "connection failed"
Also when only the USB cabel is connected on the teensy 3.2.
I also tried two different ST4 cabel. But without success.

Maybe the problem is the display? The pins are VDD, GND, SCK, SDA. The order of pin (GND,VCC) are differnt between the SHC PCB and the display.
So I did make sure that GND and VCC are right connected with SHC PCB and the display.
But maybe the problem is the pin *SCK*? On the PCB this pin namend SCL.

Thanks for your support!


helmutliebenau@...
 

I am sure that the ST4 cabel is the right one. This cabel was include in my astrocam Alccd.
Pin 1 is 5V and Pin 2 is GND. That I measured before.

Dave Schwartz
 

That was obviously correct because you're SHC at least powered up when you switched the controller on. The 'Connection Failed' message indicated that the required exchange of signals on two of the control lines did not complete successfully. Common causes are the cable or the resistor networks being missing or having been installed backward. On the STM32 controller PCB, the pad for pin 1 of the device is square (pin 1 of the resistor network device is marked with a dot).

On 2020-01-12 3:27 p.m., helmutliebenau@... wrote:
I am sure that the ST4 cabel is the right one. This cabel was include in my astrocam Alccd.
Pin 1 is 5V and Pin 2 is GND. That I measured before.

helmutliebenau@...
 

This I also checked. The resistor network with the dot marked is on square on the PCB. Both the 5 pin and the 9 pin resistor. The same I checked for the OnStep PCB.

Dave Schwartz
 

Then I'm out of ideas.

I haven't used a Teensy-based SHC with the STM32 controller but when I was validating the ESP32 SHC, I did verify that it worked with an early version of the ESP32 controller so have confidence that the inverse is also true and thus the SHC's are interchangeable. It did take a few tries to get the signalling correct - involving the use of an oscilloscope to sniff the 12.5HZ signals on pin 3 and 6.


On January 12, 2020 4:17:51 PM EST, helmutliebenau@... wrote:
This I also checked. The resistor network with the dot marked is on square on the PCB. Both the 5 pin and the 9 pin resistor. The same I checked for the OnStep PCB.

--
Sent from my Android device with K-9 Mail. Please excuse my brevity.

Howard Dutton
 

How long is the cable from the SHC to OnStep?

helmutliebenau@...
 

1,5m

Howard Dutton
 

That length should be ok.  I use longer.

helmutliebenau@...
 

Following pin connection between Teensy 3.2 and STM32 are exist when the ST4 cabel is connected (SHC with OnStep).

     Teensy            STM32
PIN 7 (TX2)  ->   PIN A6 (DEC-)
PIN 8 (RX2) ->    PIN A7 (DEC+)
PIN 6            ->   PIN B1 (RA-)
PIN 9            ->   PIN B0 (RA+)
VIN               ->   5V
GND             ->   GND

Anyone knows this is correct?

Howard Dutton
 

On Mon, Jan 13, 2020 at 08:18 AM, <helmutliebenau@...> wrote:
Following pin connection between Teensy 3.2 and STM32 are exist when the ST4 cabel is connected (SHC with OnStep).

     Teensy            STM32
PIN 7 (TX2)  ->   PIN A6 (DEC-)
PIN 8 (RX2) ->    PIN A7 (DEC+)
PIN 6            ->   PIN B1 (RA-)
PIN 9            ->   PIN B0 (RA+)
VIN               ->   5V
GND             ->   GND

Anyone knows this is correct?

That's wrong.

Howard Dutton
 

The Wiki describes the connection point.
https://onstep.groups.io/g/main/wiki/Smart-Hand-Controller

The RJ12 on the SHC is for an optional pass-through ST4 port guiding interface (for plugging a camera into for example.)  The 3D printed case only works if that jack is omitted.  The cable exists the PCB bottom (left side as shown below) between the four holes.  The four holes are for nylon ties (zip strips) as strain relief, this allows for a nice compact SHC case.

helmutliebenau@...
 

Ok, this is my problem. I'm using the RJ12 connector....
I will look again in the wiki and connect the ST4 cable on the right connention point.

Thank you Howard!

helmutliebenau@...
 

Now it works!

Thank you!