User Manual

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http://www.uugear.com/portfolio/change-the-pin-that-used-by-witty-pi/
GPIO-2 and GPIO-3 are for I
2
C communication between Raspberry Pi and the RTC
chip (DS3231). I
2
C devices are identified by I
2
C address, and they can share the I
2
C
pins as long as they have different I
2
C addresses.
Witty Pi Mini doesn’t actually use the TXD pin (it only monitors it). So using serial port
for data transaction will not be a problem.
Is Witty Pi Mini Compatible with “Other Hardware”?
Please understand that we might not have the hardware you have on hand, and even
if we have, it is difficult for us to make tests on all these hardware with Witty Pi Mini.
Fortunately, it is not that difficult to figure out the answer by yourself. Basically you just
need to consider the I
2
C address and GPIO pins used by the “Other Hardware”.
If the “Other Hardware” uses 0x68 I
2
C address, it will be a confliction with Witty Pi’s
RTC chip and you can not use it with Witty Pi together.
If the “Other Hardware” doesn’t use any GPIO pin that used by Witty Pi, and it doesn’t
use 0x68 I
2
C address, then it should be compatible with Witty Pi.
If you have no idea which I
2
C address (if applicable) or GPIO pins are used by the
“Other Hardware”, please contact its developer, as they certainly know their hardware
and can provide you accurate information about it.
Witty Pi Mini dose not boot?
Some customers meet the situation that Witty Pi Mini only boot Raspberry Pi for a few
seconds, and then shutdown Raspberry Pi with or without lighting the white LED first.
Remarks: you may need to disconnect Witty Pi Mini from your Raspberry Pi, and
power on Raspberry Pi only for troubleshooting.
There are some possible reasons that can cause this kind of problem:
1. The OS was installed via NOOBS, and boot menu was not skipped
If you have a display connected to your Raspberry Pi during the booting, and you
have not saw the Raspberry Pi logo before Witty Pi Mini cuts the power, then it is the
case.
Please read the “Before Installation” section first, and make sure to skip the NOOBS
boot menu. Otherwise the boot menu will delay the booting, and hence the TX pin
doesn’t raise fast enough, so Witty Pi Mini thinks the OS is down and cuts the power
directly.