Clock Module 28X2 Pins
- Thread starter jopooze
- Start date
hippy
Ex-Staff (retired)
If using PE6 the "Input/Output Table" option in Workspace Explorer will bring up a diagram and listing of pins. For the 28X2 -
Leg 14, C.3, I2C SCL
Leg 15, C.4, I2C SDA
"PICAXE Manual 1 - Getting Started" also contains PICAXE pinout diagrams.
The DS1307 OUT/SWQ signal can go to any digital input pin or can be left unconnected if not used. Note it is open collector so will need a pull-up to be used.
Leg 14, C.3, I2C SCL
Leg 15, C.4, I2C SDA
"PICAXE Manual 1 - Getting Started" also contains PICAXE pinout diagrams.
The DS1307 OUT/SWQ signal can go to any digital input pin or can be left unconnected if not used. Note it is open collector so will need a pull-up to be used.
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hippy
Ex-Staff (retired)
Sorry that was my typo earlier; I have now corrected that.
Perhaps it's how you are wiring things up ?
If the "experimentation board" is an AXE091 then you need to use the shorter set of pin contacts on the left, between the two sets of 40-pin contacts, to get at SCL. It's also worth checking you haven't got the I2C bus wires crossed over.
If it's not that then perhaps post a photo showing how you have things connected. It might also be worth posting your 28X2 code and describing exactly how it is not working manifests itself.
No luck still. I did have the wires connected to the wrong set of pins as explained by Hippy but nothing nevertheless. I've added some pictures. No lying here, it's a tad messy.
http://imgur.com/a/9iRCb
Also here's the code I'm working with: http://hastebin.com/sasovecafa.vbs
I've purposely not revealed the jungle that the rest of my wiring is because I know it works; I used it with the 18M2 and it was perfect.
http://imgur.com/a/9iRCb
Also here's the code I'm working with: http://hastebin.com/sasovecafa.vbs
I've purposely not revealed the jungle that the rest of my wiring is because I know it works; I used it with the 18M2 and it was perfect.
I've taken the 1-wire iButton reader and the screen out so you can see a bit clearer.
http://imgur.com/a/c1yyq
http://imgur.com/a/c1yyq
Have a look here. Curing-a-locked-up-i2c-bus
Use something like IrfanView to resize\resample them to make them smaller.
inglewoodpete
Senior Member
If you're using windows, then open your pictures in Paint and scale them down (Home Tab>Resize) eg 70% and save them to a new file. It's too easy - you don't need paintshop.
I have to agree with other comments: it's really hard to tell if you have the scl and sda wires in the right sockets with the angle you had your camera at. Also, try to improve the lighting with another photo.
StigOfTheDump
Senior Member
I haven't got an AXE091 to check, but your green wire at the left of the picture in post 7 looks to be in the 13th hole.
hippy
Ex-Staff (retired)
Agreed, and the connection is to the 40-pin socket adjacent to the chip. It should, as described earlier, be to the shorter pin socket to its left. It isn't clear if the right wire is in the leg 15 (27) hole either.
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hippy
Ex-Staff (retired)
I2C and HI2C are the same commands with different names and syntax so it is unlikely that is the cause of any problems.
It is still likely to be wiring issue so it would be best if you post a photo of your circuit with unnecessary wiring removed then members can check that it is wired correctly.
It is still likely to be wiring issue so it would be best if you post a photo of your circuit with unnecessary wiring removed then members can check that it is wired correctly.
hippy
Ex-Staff (retired)
The following program worked for me on an AXE091 board, 28X2 and DS1307. Just two wires -
Leg 14, C.3, SCL
Leg 15, C.4, SDA
After a short delay, after download or power-cycling, you should see an incrementing display as follows -
If not, check the two wires go to the correct legs and correct connection points, that you have a 5V supply to the PICAXE and DS1307, check the backup battery or the DS1307 Vbat is connected to 0V.
Leg 14, C.3, SCL
Leg 15, C.4, SDA
Code:
#Picaxe 28X2
#No_Data
#Terminal 9600
Pause 2000
SerTxd( "DS1307 Test", CR, LF )
Pause 1000
SerTxd("READY ")
HI2cSetup I2cMaster, $D0, I2cSlow, I2cByte
SerTxd("SETUP ")
HI2Cout $0,(0,0,0,0,0,0,0,$10)
SerTxd("WRITE")
SerTxd(CR,LF)
b8 = -1
do
Pause 100
HI2cIn $0,(b0,b1,b2,b3,b4,b5,b6,b7 )
If b0 <> b8 Then
b8 = b0 : Gosub ShowHex
b8 = b1 : Gosub ShowHex
b8 = b2 : Gosub ShowHex
b8 = b3 : Gosub ShowHex
b8 = b4 : Gosub ShowHex
b8 = b5 : Gosub ShowHex
b8 = b6 : Gosub ShowHex
b8 = b7 : Gosub ShowHex
SerTxd( CR,LF)
b8 = b0
End If
loop
ShowHex:
b9 = b8 / $10 + "0"
If b9 > "9" Then : b9 = b9+7 : End If
SerTxd( b9 )
b9 = b8 & $0F + "0"
If b9 > "9" Then : b9 = b9+7 : End If
SerTxd( b9, " " )
Return
Code:
DS1307 Test
READY SETUP WRITE
00 00 00 00 00 00 00 10
01 00 00 00 00 00 00 10
02 00 00 00 00 00 00 10
03 00 00 00 00 00 00 10
[i]etc[/i]
hippy
Ex-Staff (retired)
The wiring seems to be correct though it would have helped to remove all unnecessary wires and use different colour wires for SDA and SCL.
That suggests there is possibly some issue with the unnecessary pull-up resistor, with your power supply, DS1307 battery supply, your code, or perhaps a faulty DS1307 or 28X2. What results do you get if you run the earlier test program ?
That suggests there is possibly some issue with the unnecessary pull-up resistor, with your power supply, DS1307 battery supply, your code, or perhaps a faulty DS1307 or 28X2. What results do you get if you run the earlier test program ?
I checked with a different DS1307, battery pack + a cable connector from a plug socket and removed the pull-up resistor so that leaves either my program or my Pic. I noticed that when using my code (the same code that worked with the other pic) the variables of the DS1307 didn't budge. They froze.
hippy
Ex-Staff (retired)
When you say "battery pack"; what voltage is that supplying ?
Also, whilst the code you had worked for other chips, have you actually tried that code on other chips in recent days with the current setup you have, or was that from 'way back when' ?
What happens when you run the code I included in post #11 ?
Also, whilst the code you had worked for other chips, have you actually tried that code on other chips in recent days with the current setup you have, or was that from 'way back when' ?
What happens when you run the code I included in post #11 ?
inglewoodpete
Senior Member
@jopooze: That output looks as if there is no "Return" statement at the end of the ShowHex subroutine.
hippy
Ex-Staff (retired)
That shows that the DS1307 is notionally working, I2C writes and reads do work. If the " If b0 <> b8 Then" command and associated "End If" are removed, the "Pause 100" increased to "Pause 1000", I would predict it to then repeatedly show "00 00 00 00 00 00 00 10" data. It would be worth testing that.
If that is the case it would seem that the DS1307 oscillator isn't working, is not incrementing its internal time. If other DS1307 chips exhibit the exact same behaviour that may point to a failed watch crystal.
That could also be double-checked by running the same test code on PICAXE chips where the RTC code used to work; it probably no longer works with those either.
Sorry I'm REALLY late to reply to this, been busy. Removing the strings you stated and increasing the pause did what you expected; not sure what that means however. You say it could be the watch crystal? How exactly could I be certain, where can I buy a new one and how can I replace it on the board?
hippy
Ex-Staff (retired)
If it is the crystal being problematic, the first thing to do is to check there are no dry joints on its legs and check its legs haven't been pushed together and are shorting. Giving the crystal body a sharp tap my kick it back into life. That's not recommended, can damage a crystal, but it doesn't seem you have a lot to lose.
You may be able to use a scope to see if there is any oscillation on the DS1307 crystal drive pins. Otherwise there is no easy way to check if the crystal is working or not. You could perhaps configure a PICAXE to use an on-chip LPOSC driven timer and see if that increments but if the DS1307 doesn't it's unlikely anything else would. It's probably easier just to replace it; simply unsolder the old one and solder in the new.
Suitable watch crystals are available from our online store ...
http://www.picaxestore.com/RES038
You may be able to use a scope to see if there is any oscillation on the DS1307 crystal drive pins. Otherwise there is no easy way to check if the crystal is working or not. You could perhaps configure a PICAXE to use an on-chip LPOSC driven timer and see if that increments but if the DS1307 doesn't it's unlikely anything else would. It's probably easier just to replace it; simply unsolder the old one and solder in the new.
Suitable watch crystals are available from our online store ...
http://www.picaxestore.com/RES038
Can't believe it's so difficult to get a flippin clock module working. I swapped AXE boards with a friend to see if the watch crystal on his worked on mine. It did not. Something is still messing with me. Hippy or someone is it possible to write a tutorial with the main tips to look out for when building a circuit with the 18M2 and the DS1307 with OLED screen. I know I've done something wrong but I don't think I'll find it fiddling for forever.
hippy
Ex-Staff (retired)
I don't think anyone else can either.
That does seem extremely odd.
There really is nothing to it. Forget any OLED display to start with. On an AXE091 board all that needs to be done is to connect two wires from the PICAXE socket to the I2C header socket and run the code in post #21.
Note that Hippy's code in post #21 sets the SQWE output on leg 7 of the DS1307 to a 1Hz frequency (but your hastebin code doesn't - you don't write to Control Register at 07H at all)
...so with Hippy's code running and with a multimeter set on volts connected to leg 7 do you see a varying voltage (0.5 sec high, 0.5 second low) on the display?
However you have to connect Leg 7 to Vcc (5 volts) with say a 10K resistor first.
If the leg 7 voltage is measured as completely stable, after writing the SQWE bit as 1 in the control register (and leaving RS0 and RS1 as zero) then it would suggest the DS1307 is not working properly.
...so with Hippy's code running and with a multimeter set on volts connected to leg 7 do you see a varying voltage (0.5 sec high, 0.5 second low) on the display?
However you have to connect Leg 7 to Vcc (5 volts) with say a 10K resistor first.
If the leg 7 voltage is measured as completely stable, after writing the SQWE bit as 1 in the control register (and leaving RS0 and RS1 as zero) then it would suggest the DS1307 is not working properly.
hippy
Ex-Staff (retired)
I think we perhaps need a reboot or refresh; need to know which PICAXE is being used, what program is being run, what board is being used, and how everything is wired, as it is no longer clear exactly what we are dealing with at this time.
The best starting point is a photo of the hardware with all unnecessary components and wiring removed.
The best starting point is a photo of the hardware with all unnecessary components and wiring removed.