[kakas]

I have tested the PCF8563 again. Inserted some code to the firmware to see the operation. The PCF8563 does not work. After sync (and stopping sync), it jumps back an hour, then starts to go backwards. (or something like that). I have replaced the chip from the same batch, same results. Then I purchased it from an other source, still it works in the same way.
It has nothing to do with Opensprinkler code or hardware.
So I replaced to DS1307 and that works fine. (VCC is 3.3V)

[kakas]

Ray, as you pointed out in your previous post:

You are right that DS1307 requires at least 4.5V VCC. So the previous version of the OpenSprinkler that used DS1307 has its VCC tied to +5V, whereas PCF8563 can work with 3.3V so its VCC is tied to 3.3V.

So wiht DS chip I have to connect VCC of DS to 5V. But the supercap’s max voltage is 3.3V, so I’m interested how the complete schematic with DS chip should look like.

[kakas]

Firmware is the latest official from github. Voltage is above 2V.
thank you for checking the functionality.
I will try the DS chips I have. What is the necessary hardware modificaton (to operate from higher voltage)?

[kakas]

I made the board, but I think schematics is the same at the RTC chip. See attached.
Experience: after NTP sync, NTP swiched off. Power off.
After re-connecting, behavior seems to be always the same. Depending on the time of the re-connection, it jumps back an hour, then starts to go backwards.

What I have already tried:
– built a new board with all chips new
– re-burned the firmware
– checked with oscilloscope that 32kHz clock is working

What else to check?

Attachments:

1. os33-brd.pdf
2. os33-sch.pdf

[kakas]

So what I experience: board is v3.3 with PCF8563. I let the backup cap get charged fully, and let NTP to sync. I switch off NTP sync, and disconnect power. After some minutes I re-connect power, and the actual time will be the time moment when I disconnected the power. I do not know if ESP saves the time and retrieves it, or the RTC provides this time. Backup voltage is OK. I have replaced the RTC and resonator, same result.

[kakas]

Schematics is v3.3. Thank you for the clear explanation, it will help a lot to find the bug.

[kakas]

Thank you Ray. I have both chips and test them. I used the 8563 first, it worked well if the AC was on. With power outage I got delays and weird dates/times. The batt voltage was 2-3V well above the required minimum for the 8563. So now I try to find the reason.
The firmware has its own clock, and periodically refreshes it from the RTC? If so, how frequently?

[kakas]

Thank you Ray, now it is clear to me.

[kakas]

I realized that I can export the libraries from the sch files. Checking them I see that the TX connector and the display connector is intentionally like that, the pins are not in one line. (So far I have seen SSD1206 with straight pin arrangement only.) The connector M04x02 pins will return to the normal position after updating the connector from the library.
An other observations: On the extender board there are DGND and GND lines, which are not interconnected in the schematics. I think they should be, as on the board they are interconnected. It confused the Eagle, so C2 has no GND connection (just hanging in the air) without airwire or warning. The GND line from RS to the GND pin should be thick conductor, as current of all loads (including the extension boards) are going through here.

Attachments:

1. 

   c2.jpg
   

2. 

   3.jpg
   

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