Serhii Solohub

Thnx Malcolm ! So, as I understand, the USB-TTL converter I mentioned above SHOULD not harm the motor board, but it's possible to have troubles in communications between the PC and the motor controller when I use this cheap chip 🙂 . Also, I may experience a troubles in Windows 10 due to lack of official drivers. I think I will measure the voltage of RXD and TXD pins and, if it it near the 5V, I [maybe] will try cause I have this converter at home. But I think I will order the FTDI EQDirect cable. Anyway, later I'm going either to use that board controller with the second mount or to sell it to someone with the good, 100% worlable cable in pair 🙂 .

malc-c, thnx for the info ! Do I understand right: in the FTDI USB-TTL converter the voltage of RX and TX is 0V (as logical 0) and 5V (as logical 1), and in the cheap USB-TTL converter voltage of RX and TX is -12V (as logical 0) and +12V (as logical 1) ? That sounds a little bit strange, and I just want to understand this fully... I see a lot of USB-TTL converters like i.e. https://aliexpress.ru/item/1875954176.html , so they may have -12V and +12V at RXD and TXD pins ? You see, I have made my own mount controller based on Arduino, as so as my friend has built his own one. But his controller has no any control from PC except several Serial port commands to sync current RA/DEC position and a GOTO-command and ST-4 guiding. Mine has the same functionality + I have made a tiny ASCOM-driver for it, so ASCOM PulseGuiding is present too. Now he wants to create a new version of his controller with full EQMOD support (what means: a full support of Synta SynScan protocol). And I helps him with the understanding of that protocol. Another my friend has bought EQDRIVE mount controller as a replacement of the stock SynScan mount controller (aka "motor board") because EQDRIVE has belt gear in stock. So I bought from him the unnecessary SynScan EQ5 mount controller (photos in attachment). It should be fully workable except of the connector that was moved to EQDRIVE to make it possible to connect EQDRIVE with motors using the stock wires. Does not matter, all I need of this is to connect it to the PC with EQMOD and see the COM port traffic to compare it with my Arduino SynScan "implementation" (such a load word 🙂 ) . I have described this to make it clear why am I trying to understand the EQDirect's peculiar properties: that is not a problem to obtain FTDI cable (except the delivery time to Ukraine), but as a person who want to work with the SynScan protocol I really want to understand the details of how EQDirect works and why cannot I use a simple USB-TTL like the one that Arduino has on its board. And I don't know the better place to ask cause on Arduino forums nobody knows anything about SynScan motor boards. So sorry for sucj a lot of questions about all of that USB-TTL's... But I really want to understand.

I just wonder... Why does the regular USB-TTL can blow a motor board ?.. What if I will plug it in the PC and solder GND, RX and TX to the RJ-45 connector, as it described on the EQMOD pre-requisits page ( http://eq-mod.sourceforge.net/reqindex.html ) : As I understand, the only thing I have to think about in that case is that USB-TTL musqt have RX and TX at 5V... Or am I wrong ?

Thnx for the reply ! looks like a regular EQMOD connection routine. I think I will try to solder the EQDir-USB or EQDIR-ST232 with myself.

Hello M40, and thnx for the reply. I have SynScan EQ5 controller, but the handset is missing. As I understand, I can (theoretically) connect a PC with EQASCOM installed to that controller using EQDirect-USB way. But, if I have understood correctly, the topicstarter had some issues with this kinf of connection. The controller needs a small repair, so I wonder whether it worth it or not, cause if I will not be able to connect EQMOD to this SynScan EQ5 without handset then I will not be able to connect it at all. After you reply, I think, it worth it to try.

Hello. So, do you need to use the handset control as intermediate dedice between PC with EQMOD and SynScan EQ5 mount controller device ?