CH340 as P1 not working

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hemant5400z
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CH340 as P1 not working

Post by hemant5400z »

Hi All i'm trying to build:
bbqkees wrote: Thursday 07 May 2015 11:42 I can confirm the cables with the HL-340 IC automatically invert the data.
I used a FTDI version before but you need to reprogram them before use. This HL-340 one is much easier to use.
However, if you cannot solder yourself you should stick to a FTDI version or similar without a DB9 connector because you can cut the wires and connect the RJ11 plug without soldering.

I bought 2 of the HL-340 cables and they work just fine with the Landis/Gyr E350 with DSMR 4.0.
http://www.ebay.nl/itm/New-USB-to-RS232 ... 1395736651

They indeed need a 1K pull-up resistor between pin 2 and 5 of the RJ11 wiring for the E350 meter. Otherwise no data shows up on the serial interface.

What you need to do is get a RJ11 telephone cable (with all 4 pins wired) and cut it off.
Also remove the blue plastic and the plug from the DB9 side of the serial cable.
This reveals the pcb, on which you can solder the wires.

Image
Image

Plug it in the meter and the Pi and it will work fine.

My device is shown as CH340 in windwos and CH341 on Linux, i have hooked up the cables like abobe except my meter is E360 3-fase running DSMR 5.0 so the resistor needs to be between 5k-10k iguess?

However when I check the power on the USB side of the cable i canmeasure 5v. When I do that on the TTL side assuming red=GND and black is 5v i get no power at all. is that correct?

Does anyone know what i'm missing here?

Cheers,

Hemant
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HansOtten
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Re: CH340 as P1 not working

Post by HansOtten »

Strange conventions in use here.

What is the RJ11 pinning?

Image

Red is usually power supply, black is ground.

The resistor is for pulling up the open collector output of the smartmeter.

Not a real problem, but there is a 1k2 resistor in the photos. Close enough, it will work.

Have a look here: http://domoticx.com/p1-poort-slimme-meter-hardware/
Raspberry Pi 4, SSD, RFlink, P1 Smart Meter. Many Zigbee devices CR2562 USB stick. Bresser via Weather Underground
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hemant5400z
Posts: 80
Joined: Monday 05 November 2018 17:41
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Re: CH340 as P1 not working

Post by hemant5400z »

Hi Thanks,

I would like to understand what the device is expecting to put on the Pins.
As I do not measure any 5v on the rj11 side of the pins.

Will this device work with a E360 3-fase?

Hemant
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erem
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Re: CH340 as P1 not working

Post by erem »

first, check with a multimeter if ground from usb side connects to ground on data side
second, for normal operations of an usb interface to serial 5v is not needed at the data side, you you may need to source that from the usb side.
i would check the 5v path with a multimeter to see if that actually is present at the data side.
Regards,

Rob
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