Todespreis
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Hey there! I'm just wondering, is it possible to display the unix time in Gmenu2x and not the time, how long the handheld is on? Is there a setting for it somewhere?
Gmenu2x displayed time
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TeDaDeS
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I don't have a GP2x sadly, but I think the GP2X is lacking an RTC (Real-Time Clock) so it doesn't remember the actual time. Classic handheld design, as an RTC costs battery.
And I assume that is the reason it only shows the time it's on instead of the actual time.
I think there was a discussion on adding an RTC add-on in the past: https://pyra-handheld.com/boards/threads/possibility-for-a-realtime-clock.26160/
And I assume that is the reason it only shows the time it's on instead of the actual time.
I think there was a discussion on adding an RTC add-on in the past: https://pyra-handheld.com/boards/threads/possibility-for-a-realtime-clock.26160/
Todespreis
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Hey! Thanks for the answer, yes, i know, the batteries... GP2X gets hard resetted every time, it goes off. But finally i found the layout of the EXT connection on the device and now i know, where all the pins are lying. And my idea is basically to put a microcontroller with an RTC and let the GP2X "ask" the microcontroller every time, the handheld goes on - what time it is? 
I want to connect them via UART and the microcontroller would work with RTC via I²C. I just don't want to mess it up with recompiling the gmenu2x ^^"
I want to connect them via UART and the microcontroller would work with RTC via I²C. I just don't want to mess it up with recompiling the gmenu2x ^^"
TeDaDeS
Forum Addict!
There are off-the-shelve modules you could use, for example:
www.dfrobot.com
Gravity: I2C DS1307 RTC Module
Gravity I2C DS1307 RTC module is an Arduino compatible real time clock, which can be used as alarm clock.
Orkie
Super Duper Mega GP Mania
If you're going to such lengths, you could always try to see if VDDRTC/VSSRTC/XTIRTC/XTORTC on the MMSP2 are exposed anywhere on the board and splice a coin cell/crystal in... Chapter 6 of the MMSP2 databook details the relevant registers.
Todespreis
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@TeDaDeS thats actually the problem - the CPU is capable of I²C, but there are no drivers for it, at least i could'nt find any. And i'm not that good at c coding, that i could write one by myself and that leads me to the second problem
@Orkie to solder an rtc module to the cpu directly would be a much more ellegant solution, but i'm just not capable of doing that and i'm too afraid to damage my unit.
My solution may be not the accurate one, but in my opinion it's the safest way to add anything. I thoughd already about it, just to make some kind of external attachement via the EXT connection, but there should be more, than just an RTC to justify an external device. Maybe i should draw it to show my thoughts in a better way
@Orkie to solder an rtc module to the cpu directly would be a much more ellegant solution, but i'm just not capable of doing that and i'm too afraid to damage my unit.
My solution may be not the accurate one, but in my opinion it's the safest way to add anything. I thoughd already about it, just to make some kind of external attachement via the EXT connection, but there should be more, than just an RTC to justify an external device. Maybe i should draw it to show my thoughts in a better way
Orkie
Super Duper Mega GP Mania
I've never heard of anybody doing it, I'm not sure anybody has ever been desperate for an RTC before. I2C is definitely exposed though, the serial number and LCD settings are stored on an I2C EERPOM - you could probably daisy chain something off that (might need a buffer): http://wiki.gp2x.org/articles/i/2/c/I2C.html
TeDaDeS
Forum Addict!
I could imagine RTC was designed into the product at one point but wasn't important enough compared to battery life or cost. So it was removed again.
Todespreis
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Oh, how cool is that! Thanks Orkie! Now it is a completely different thing and definitely worth trying
