TheBackShed.com

Forum Index : Microcontroller and PC projects : Small graphic steps

Author

Message

VK2AHB
Regular Member

Joined: 28/07/2022
Location: Australia
Posts: 51

Posted: 02:51am 08 Sep 2022

Copy link to clipboard

Print this post

I've worked out a bit about display and number boxes and how to put values in them.

Still learning. This is with the DS18B20 and RTC connected. Also have a DHT11 but it's not playing this time.

Occasionally, seemingly randomly, the screen goes white and I have to rest the 'mite. Maybe I bumped the wires.

Paul VK2AHB

Geoffg

Guru

Joined: 06/06/2011
Location: Australia
Posts: 3308

Posted: 03:57am 08 Sep 2022

Copy link to clipboard

Print this post

The screen going white (or rather grey) is the sign of a reset of the LCD or the processor.

You are using the PCB for the VGA version of the PicoMite firmware which does not support LCD displays. I'm not sure what pin conflicts you would have using the PicoMite version (which does support LCD panels) on the VGA board but that may be the cause.

What version of the firmware are you using? The PicoMite or PicoMiteVGA version?

Geoff

Geoff Graham - http://geoffg.net

VK2AHB
Regular Member

Joined: 28/07/2022
Location: Australia
Posts: 51

Posted: 08:22am 08 Sep 2022

Copy link to clipboard

Print this post

I'm using the PicoMite firmware. It works well, then randomly resets. Hitting the reset button on the board doesn't always bring the black screen back. It takes a few goes sometime.

Paul

phil99

Guru

Joined: 11/02/2018
Location: Australia
Posts: 2832

Posted: 09:00am 08 Sep 2022

Copy link to clipboard

Print this post

Re the DHT11, to get the correct T & H only read it once every 2 seconds.

Do : Bitbang humid gp0, T, H, 1 : pause 2000 : ? T, H : loop 'DHT11, whole Deg. only

To get the tenths of degrees try this

'Reading DHT11 sensor using DHT22 BITBANG HUMID function.
'Requires 2 pins. eg link pins GP0 & GP1 to DHT11 signal pin.
' It gives 10ths of degrees. The normal DHT11 option does not.
Do
pin(GP1)=1
setpin GP1,dout,oc
pause 2000
pulse 20
pause 19
BitBang Humid GP0,T11,RH11
if RH11=1000 and T11=1000 then
RH=1000 : T=1000
else
T = fix(T11/25.6) + ((T11*10) MOD 256)/10
RH = fix(RH11/25.6)
Endif
setpin GP1,off
print "Temp ";T,"Humidity ";RH
loop

More info.
https://www.thebackshed.com/forum/ViewTopic.php?TID=13832&P=3#174519

Also

RTC GetReg 17,Temp : ? Temp 'get temp. from DS3231 RTC

Mixtel90

Guru

Joined: 05/10/2019
Location: United Kingdom
Posts: 8304

Posted: 10:07am 08 Sep 2022

Copy link to clipboard

Print this post

@VK2AHB
Interesting, Paul. That PCB wasn't designed to be able to use LCD displays. :)
How have you got it connected? Which signals on which GP pins?

GP18, GP19, GP20 and GP21 should be avoided as they have resistors and diodes to GND, loading the outputs.

Also, I'd highly recommend that you use female/female Dupont leads to connect the display and do without that little breadboard. They can give wonky connections, especially with the weight of a display levering on the el-cheapo Chinese tinplate sockets.
Edited 2022-09-08 20:09 by Mixtel90

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

phil99

Guru

Joined: 11/02/2018
Location: Australia
Posts: 2832

Posted: 11:45am 08 Sep 2022

Copy link to clipboard

Print this post

Typo in code above, fixed here.

'Reading DHT11 sensor using DHT22 BITBANG HUMID function.
'Requires 2 pins. eg link pins GP0 & GP1 to DHT11 signal pin.
' It gives 10ths of degrees. The normal DHT11 option does not.
Do
�pin(GP1)=1
�setpin GP1, dout, oc
�pulse GP1, 20
�pause 19
�BitBang Humid GP0,T11,RH11
�if RH11=1000 and T11=1000 then
�� RH=1000 : T=1000
� else
� �T = fix(T11/25.6) + ((T11*10) MOD 256)/10
� �RH = fix(RH11/25.6)
�Endif
�setpin GP1,off
RTC GetReg 17,TempRTC
�print "Temp ";T,"Humidity ";RH,"TempRTC";TempRTC,time$
�pause 2000
loop

PS Ensure there is a pullup on the data pin. Probably one on the module but best to be sure.
Edited 2022-09-08 22:31 by phil99

VK2AHB
Regular Member

Joined: 28/07/2022
Location: Australia
Posts: 51

Posted: 12:26pm 08 Sep 2022

Copy link to clipboard

Print this post

Well you know what they say: 'Fools rush in ...'
I'm using pins 21, 22, 24 for the display and 25 the DHT11.

I'm pretty sure the DHT11 was working in VGA mode, not sure what pin I used then.

Paul

stanleyella

Guru

Joined: 25/06/2022
Location: United Kingdom
Posts: 2681

Posted: 04:26pm 08 Sep 2022

Copy link to clipboard

Print this post

It is true breadboard birds nest wiring is prone to faults.
Wire it with female connectors as suggested previous post is more reliable.

stanleyella

Guru

Joined: 25/06/2022
Location: United Kingdom
Posts: 2681

Posted: 05:00pm 08 Sep 2022

Copy link to clipboard

Print this post

I still use bread boards because just testing but got to solder a reliable board.
Do not say pcb... strip board and hope no capacitance problems because of parallel tracks.
If you look at this the wrong way it will crash.

Print this page

To reply to this topic, you need to log in.