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Grogster

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Posted: 05:47am 11 Feb 2020

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Hi all.

I needed a wireless link that would fit into a standard single wall-plate, so I came up with this:

What I needed, was a simple door-switch that would send a certain code to a base-unit, so I came up with this design, but expanded it so that not only the switch input(SW) is available, but also all of the unused I/O pins for maximum flexibility.

The PCB is designed to fit into a PDL 600-series single wall-plate(a blank one such as 650VH), as in the system I wanted to use it with, all the other call-points etc were on single wall-plates, and powered by a common 12v DC-bus via 4-core security cable.

If anyone is interested in this, I can build a constructors pack and make it available for download from my website along with demo code, BOM etc.

The PCB is still in alpha, so it might have errors, but I will discover these when I build the first few - which have been ordered.

Smoke makes things work. When the smoke gets out, it stops!

Chopperp

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Joined: 03/01/2018
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Posted: 07:55am 11 Feb 2020

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Hi Groggs

Good timing. I put in an order for some HC-12's from you yesterday & just sat down to plan out a bit of a MM radio network to get rid of some hard wiring I have around the place.

Your board probably would suit one of my needs.

Could you confirm that the board itself is about 65-66mm wide?

Thanks

Brian

ChopperP

Bill7300
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Joined: 05/08/2014
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Posted: 09:51pm 11 Feb 2020

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Good timing but also good thinking on the housing, Grogs. Let us know once you have the board up and running.

Bill

Bill

Grogster

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Posted: 11:15pm 11 Feb 2020

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@ Chopperp: Yes, 66mm x 89mm. Designed to be a perfect fit in the rear of a PDL 600-series blank wall plate. It will fit either the 650VH or the 650BVH.

Assuming you can get the PDL wall-plate series in Australia? I would expect so - yes?
I think that PDL are now called Schneider Electrical, but the codes are still the same so I understand.

@ Bill7300: Will do.

Smoke makes things work. When the smoke gets out, it stops!

palcal

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Posted: 11:56pm 11 Feb 2020

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Clipsal and HPM both have them here in OZ, just a standard wall plate and mounting block if you want.

"It is better to be ignorant and ask a stupid question than to be plain Stupid and not ask at all"

Chopperp

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Posted: 12:15am 12 Feb 2020

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Thanks Groggs.

ChopperP

Andrew_G
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Posted: 09:53pm 12 Feb 2020

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Groggs,
This could be very useful to receive then re-broadcast HC-12 messages around any dead spots in the house.
(but I'm not yet sure if SWMBO will allow me to put in more wall plates . . . any chance they could fit behind, say, operative light switch plates - without contravening safety/regs?? - probably not.)

I respect that you have done this for a particular need but two quick comments:
- could they (optionally) be powered by 5V (rather than 9 - 12). Is it as simple as jumpering VR1 out?
- can the 12V go as far as, say, 12.9V for battery power (if not a separate VR could be used) ?

Cheers,

Andrew

Grogster

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Posted: 03:37am 13 Feb 2020

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Hello.

You COULD hide the PCB in the wall-cavity behind an existing wall-plate, but as you suspect, there are electrical regulation issues there.

Two spring to mind: (1) Separation standards between 230v and low-voltage stuff, and (2) you can't install a plug-pack inside the wall-cavity, and you are also not supposed to drop a low-voltage cable down the same holes in the wall as the 230v stuff - but whatever you do is up to yourself. ;)

In my case, all the cabling is 0.5mm(well, 0.44mm) 4-core low-voltage security cable that just loops in and out anywhere it is needed, all fed from a master PSU and backup battery. That is is the main reason for the 1000uF cap on the DC input - just to decouple the DC power a bit due to the lengths of the cable runs. With the circuit running from 5v or so, that gives us 7v or so of headroom to play with to allow for voltage-drop on the cable - not that I have ever seen an issue with that at the currents being talked about here.

As to your other question, yes, you can just not install the 5v regulator, and feed the circuit from 5v directly. Voltage-drop on HC12 transmit MIGHT be an issue, cos you then won't have the juicy 1000uF decoupling cap to help decouple the input voltage.

The 5v regulator is my old faithful MCP1703A-50, and it can have up to 16v applied to its input, so that becomes around 16.6v ABSOLUTE MAXIMUM input, taking the 0.6v dropped across D1. It's never a good idea to run things right at the threshold though, so I would not push the voltage up above about 14v maximum. The circuit will be happy at 13.8v - which is a very common single-supply voltage used in many security system installs.

Smoke makes things work. When the smoke gets out, it stops!

Andrew_G
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Posted: 09:42pm 13 Feb 2020

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Hi Groggs,
Thanks for that.
We are about to decide IF we we are to go ahead with building a new house. IF we do I'll be running lots of Cat 5 cable and using HC-12s too.
Your wireless nodes might be very useful.

Please keep us posted.
Cheers,

Andrew

BrianP
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Joined: 30/03/2017
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Posted: 09:52pm 13 Feb 2020

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Andrew_G said Hi Groggs,
Thanks for that.
We are about to decide IF we we are to go ahead with building a new house. IF we do I'll be running lots of Cat 5 cable and using HC-12s too.
Your wireless nodes might be very useful.

Please keep us posted.
Cheers,

Andrew

Just thinking (idly)...
Would it not be better to run cat6 cabling to future-proof a (little) bit more?

As I said, just thinking...

Andrew_G
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Posted: 10:11pm 13 Feb 2020

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Thanks Brian,
Good point and I'm always open to ideas.
(I had asked here about 18 months ago so I'll do more research before deciding).

I don't want to hijack this thread.

Cheers,

Andrew

Grogster

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Posted: 02:03am 14 Feb 2020

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You're not.

I would also go for CAT6, cos then you can guarantee 1Gb network speed.
CAT5 does work at 1Gb if that is all you have, but the speed won't be optimum.
1Gb on CAT5 is still going to be faster then 10/100 on CAT5, but if you end up building a new house, then I would definitely go for the CAT6.

Smoke makes things work. When the smoke gets out, it stops!

Andrew_G
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Posted: 03:06am 14 Feb 2020

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Thanks Groggs

Your node is still a great idea.
(its also got me thinking of why not a MM with touch screen LCD in there . . .)

Andrew

CaptainBoing

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Posted: 10:05am 14 Feb 2020

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LOL. CAT6 meh.

I had to throw a link together really quickly and all I had was 4-pair CW1308 telephone cable. I wired it for 1G (not expecting much) thinking if it's no good it'll be alright for an auto-negotiated 100M and even then 10M would be fine (only 30m to the back of the sky box from the backbone). Absolutely no issues whatsoever! 1G sprang up like a good 'un and 2 decades later it is still fine with not so much as a dropped packet.

Guess I am a lucky slob �

word of advice for new-builds/refurbs. Use a colour code. Network cable comes in all colours, choose one and stick with it so you know what is what when opening up an access hatch (and label them to)

jus' sayin
Edited 2020-02-14 20:17 by CaptainBoing

Grogster

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Posted: 06:45am 19 Feb 2020

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My PCB's have arrived, so I have built one into a PDL 650VH blank wall-plate:

Demo code:

Quote 'Wireless node 1A
'(C) 2020, Rictech

'VERSION: 1A1 [19/02/2020] - Initial release.

Option Explicit
OPTION AUTORUN ON
CONST SW=14,J1=15,HB=16,HC12=23,PIEZO=24
SetPin SW,DIN
SetPin J1,DIN,PULLDOWN
SetPin HB,DOUT
SetPin HC12,DOUT:Pin(HC12)=1
SetPin PIEZO,DOUT
DIM STRING A$
DIM INTEGER X,Y,Z
Open "COM1:1200" as #1 'COM port to HC12 module
Settick 1000,HEARTBEAT 'Start the heartbeat LED blinker
Pulse PIEZO,250
Select CASE PIN(J1)
Case 1
Print "Transmit mode."
DO
DO
WATCHDOG 10000
LOOP UNTIL pin(SW)=0 'Wait till door opened
A$="DOORO"
Print #1,A$
DO
WATCHDOG 10000
LOOP UNTIL PIN(SW) 'Wait till door closed
A$="DOORC"
Print #1,A$
LOOP
CASE 0
Print "Receive mode."
DO
DO
WATCHDOG 10000
LOOP UNTIL loc(#1)
Pause 250 'Allow all of message to arrive in buffer
A$=INPUT$(LOC(#1),#1) 'Suck message from buffer
IF A$="DOORO" THEN
DO
Pulse PIEZO,250
WATCHDOG 10000
LOOP UNTIL LOC(#1)
ENDIF
Pause 250 'Allow all of message to arrive in buffer
A$=INPUT$(LOC(#1),#1) 'Suck message from buffer
A$="" 'Discard whatever the message was
LOOP
END SELECT

SUB HEARTBEAT 'Heartbeat LED driver
Pulse HB,5
END SUB

'===================================================================================
'HC12 programmer - run from command line to initially setup a new unit's HC12 module
'===================================================================================
Sub SETUP_HC12
Local D$
SetPin 23,DOUT 'HC12 SET line
Open "COM1:9600" As #1 'Default baud-rate for a new HC12 is 9600...
Pin(23)=0 'Enter command mode
Pause 250 'Wait for module to respond
Print "Now attempting to configure new HC12 module @ 9600 baud..."
Print
Print "<HELLO MODULE?> ";
Print #1,"AT"
Pause 250
D$=Input$(Loc(#1),#1) 'Suck HC12 response from buffer
Print D$
Pause 250
Print "<SET 1200 BAUD> ";
Print #1,"AT+B1200"
Pause 250
D$=Input$(Loc(#1),#1) 'Suck HC12 response from buffer
Print D$
Pause 250
Print "<SET CHANNEL 63(458.2MHz)> ";
Print #1,"AT+C063"
Pause 250
D$=Input$(Loc(#1),#1) 'Suck HC12 response from buffer
Print D$
Pause 250
Print "<SET FU4 MODE> ";
Print #1,"AT+FU4"
Pause 250
D$=Input$(Loc(#1),#1) 'Suck HC12 response from buffer
Print D$
Pause 250
Print "<SET 25mW OUTPUT> ";
Print #1,"AT+P6"
Pause 250
D$=Input$(Loc(#1),#1) 'Suck HC12 response from buffer
Print D$
Pause 250
Pin(23)=1 'Exit command mode - changes take effect now!
Print "DONE! Execute CHECK_HC12 to confirm settings."
Close #1
End Sub

End

Sub CHECK_HC12 'Must run from console.
Local D$
SetPin 23,dout
Open "COM1:1200" As #1 '1200 baud now, as module should be programmed...
Pin(23)=0 'Enter command mode
Pause 250 'Wait for module to respond
Print "QUERY MODULE:"
Print
Print #1,"AT+RX"
Print
Pause 1000
D$=Input$(Loc(#1),#1)
Pin(23)=1
Print D$
Print
Print "DONE."
Close #1
End Sub

Install J1 for transmit mode, or leave it off for receive mode.
Only the switch input(SW) is supported in this code, but you could easily expand it to do other things, or take advantage of the extra I/O pins.

Smoke makes things work. When the smoke gets out, it stops!

RonnS
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Joined: 16/07/2015
Location: Germany
Posts: 120

Posted: 11:18pm 19 Feb 2020

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Andrew_G
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Posted: 12:25am 20 Feb 2020

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Hi Groggs,

Very good. Some quick comments/questions:
- the Setup and Check subroutines are great - I use Rob's program, but this is a �great option too

- where does your switch go? I presume elsewhere? Or, you might be able to use spacers at the four screws with a switch in the outer plate? (in a subsequent version one might find space near the centre to drill a hole for one??)
- I'm assuming Jumper 1 is just for your code? One could ignore that and still "suck" and Print to the HC-12?
- I'm still struggling to get noise out of a MM - is your piezo loud enough, what ID does it have and from where? {Edit: I just noticed that it is from the 9-12V supply - that would help. I've been restricting myself to 5V }

Cheers,

Andrew
Edited 2020-02-20 10:28 by Andrew_G

Grogster

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Posted: 06:32am 21 Feb 2020

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Howdy.

Switch is a reed-switch and magnet on a door.
J1 is just so the code knows weather this unit is a transmitter or a receiver. You could just ignore that and do whatever you like.

Most piezo beepers with built-in drivers are designed to run from 12v.
They still work at 5v, but they are very quiet.
Most of them won't work at all at 3v3.

You need a transistor buffer, which is what I am using in this PCB.
The piezo is connected to 12v, and the 3v3 I/O pin on the MM drives the transistor buffer. They are plenty loud enough like that.

Here is updated code, cos I found bugs in the first version I posted above:

Quote 'Wireless node 1A
'(C) 2020, Rictech

'VERSION: 1A1 [19/02/2020] - Initial release.

Option Explicit
OPTION AUTORUN ON
CONST SW=14,J1=15,HB=16,HC12=23,PIEZO=24
SetPin SW,DIN
SetPin J1,DIN,PULLDOWN
SetPin HB,DOUT
SetPin HC12,DOUT:Pin(HC12)=1
SetPin PIEZO,DOUT
DIM STRING A$
DIM INTEGER X,Y,Z
Open "COM1:1200" as #1 'COM port to HC12 module
Settick 1000,HEARTBEAT 'Start the heartbeat LED blinker
Pulse PIEZO,250
If MM.WATCHDOG then 'Four short beeps to audibly indicate watchdog reset
Print "Watchdog reset the unit."
FOR X=1 to 4
Pulse PIEZO,50
Pause 150
NEXT
ENDIF
Select CASE PIN(J1)
Case 1
Print "Transmit mode."
DO
DO
WATCHDOG 10000
LOOP UNTIL pin(SW) 'Wait till door opened
A$="DOORO" 'Door Open message
Print #1,A$ 'Transmit the message
Pause 500 'De-bounce delay
DO
WATCHDOG 10000
LOOP UNTIL PIN(SW)=0 'Wait till door closed
A$="DOORC" 'Door Closed message
Print #1,A$ 'Transmit the message
Pause 500 'De-bounce delay
LOOP
CASE 0
Print "Receive mode."
DO
DO
WATCHDOG 10000
LOOP UNTIL loc(#1)
Pause 250 'Allow all of message to arrive in buffer
A$=INPUT$(LOC(#1),#1) 'Suck message from buffer
A$=LEFT$(A$,5) 'Drop the CR and LF from the message
Select Case A$
CASE "DOORO" 'Door open message
DO
Pulse PIEZO,250
Pause 1000
WATCHDOG 10000
LOOP UNTIL LOC(#1)
A$="" 'Clear A$ for next time
CASE "DOORC" 'Door closed message
Pulse PIEZO,100
Pause 250
Pulse PIEZO,100
Pause 250
WATCHDOG 10000
A$="" 'Clear A$ for next time
CASE ELSE 'Any other message...
If LOC(#1) then 'If there is anything at all in the buffer...
A$=INPUT$(LOC(#1),#1) '...then suck it out of the buffer...
ENDIF
WATCHDOG 10000
A$="" '...and then dispose of whatever it was so buffer is always empty.
END SELECT
LOOP
END SELECT

SUB HEARTBEAT 'Heartbeat LED driver
Pulse HB,5
END SUB

'===================================================================================
'HC12 programmer - run from command line to initially setup a new unit's HC12 module
'===================================================================================
Sub SETUP_HC12
Local D$
SetPin 23,DOUT 'HC12 SET line
Open "COM1:9600" As #1 'Default baud-rate for a new HC12 is 9600...
Pin(23)=0 'Enter command mode
Pause 250 'Wait for module to respond
Print "Now attempting to configure new HC12 module @ 9600 baud..."
Print
Print "<HELLO MODULE?> ";
Print #1,"AT"
Pause 250
D$=Input$(Loc(#1),#1) 'Suck HC12 response from buffer
Print D$
Pause 250
Print "<SET 1200 BAUD> ";
Print #1,"AT+B1200"
Pause 250
D$=Input$(Loc(#1),#1) 'Suck HC12 response from buffer
Print D$
Pause 250
Print "<SET CHANNEL 63(458.2MHz)> ";
Print #1,"AT+C063"
Pause 250
D$=Input$(Loc(#1),#1) 'Suck HC12 response from buffer
Print D$
Pause 250
Print "<SET FU4 MODE> ";
Print #1,"AT+FU4"
Pause 250
D$=Input$(Loc(#1),#1) 'Suck HC12 response from buffer
Print D$
Pause 250
Print "<SET 25mW OUTPUT> ";
Print #1,"AT+P6"
Pause 250
D$=Input$(Loc(#1),#1) 'Suck HC12 response from buffer
Print D$
Pause 250
Pin(23)=1 'Exit command mode - changes take effect now!
Print "DONE! Execute CHECK_HC12 to confirm settings."
Close #1
End Sub

End

Sub CHECK_HC12 'Must run from console.
Local D$
SetPin 23,dout
Open "COM1:1200" As #1 '1200 baud now, as module should be programmed...
Pin(23)=0 'Enter command mode
Pause 250 'Wait for module to respond
Print "QUERY MODULE:"
Print
Print #1,"AT+RX"
Print
Pause 1000
D$=Input$(Loc(#1),#1)
Pin(23)=1
Print D$
Print
Print "DONE."
Close #1
End Sub

This version has a long beep for the door being open, and 2x short beep when the door is closed. Any other message is sucked out of the buffer and disposed of to keep the buffer empty, so you don't get corrupted messages.

Smoke makes things work. When the smoke gets out, it stops!

Andrew_G
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Joined: 18/10/2016
Location: Australia
Posts: 839

Posted: 11:10pm 21 Feb 2020

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G'day,
thanks for that Groggs. All good stuff.

Can you let us know if/when you go into "production" (and whether it is a full kit or PCB or what?).
I could use a few - but no rush.

Cheers,

Andrew

Chopperp

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Joined: 03/01/2018
Location: Australia
Posts: 1032

Posted: 07:10am 22 Feb 2020

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Andrew_G said G'day,
thanks for that Groggs. All good stuff.

Can you let us know if/when you go into "production" (and whether it is a full kit or PCB or what?).
I could use a few - but no rush.

Cheers,

Andrew

Like wise

Brian

ChopperP

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