Stupid Question: Why can't you use internal rtc, by config?

Discussion of developmental aspects of the MiSTer Project.
goofyseeker3
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Stupid Question: Why can't you use internal rtc, by config?

Unread post by goofyseeker3 »

if the hps can have time, by linux, why cant you just ask the linux to provide the time, you can set it to whatever 1999 you want

edit: set the fpga to a certain speed, then make your own clock
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jdeberhart
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Re: stupid question: why cant you use internal rtc, by config?

Unread post by jdeberhart »

Even linux has to get the time somehow; the DE10 nano has no onboard clock battery to keep time when it's powered off. The addon fixes that problem. If you want a clock without using the clock board, either use a wired or wireless internet connection so it can fetch the time via NTP.
goofyseeker3
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Re: stupid question: why cant you use internal rtc, by config?

Unread post by goofyseeker3 »

So it is the same as a computer that has its battery empty, asking for time, all the time, you could manually input the time too.

What if you sleep the board, DE10, with either from battery or wall power, would it hold the time?
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Re: stupid question: why cant you use internal rtc, by config?

Unread post by rhester72 »

DE-10 has no sleep states (or power control of any form), so the question is meaningless.
goofyseeker3
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Re: stupid question: why cant you use internal rtc, by config?

Unread post by goofyseeker3 »

You only need time when dealing with "the world".

You can have it powered always.
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Re: stupid question: why cant you use internal rtc, by config?

Unread post by jca »

What are you trying to accomplish?
goofyseeker3
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Re: stupid question: why cant you use internal rtc, by config?

Unread post by goofyseeker3 »

Getting rid of the two boards and make it compatible with de10-standard and SoCKit dev-kit.
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Re: stupid question: why cant you use internal rtc, by config?

Unread post by jca »

Now I understand. MISTer on a single board. But these boards are not cheap. Regarding the clock: it is automatically updated by MISTer is you are connected to the net, if not you can set it up at the console or add a RTC chip but it would defeat the purpose of having it run on an out of the box board.
goofyseeker3
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Re: stupid question: why cant you use internal rtc, by config?

Unread post by goofyseeker3 »

sockit dev-kit is around 80usd, from arrow, i guess the de-10 standard could be mass ordered to be the same price.
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Re: stupid question: why cant you use internal rtc, by config?

Unread post by jca »

sockit dev-kit from Arrow $66.03, sockit dev-kit from Terasic $350.00 and it looks like it is the same thing. :shock: :shock: :shock:
DE10-Standrad from Terasic $350.00
goofyseeker3
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Re: stupid question: why cant you use internal rtc, by config?

Unread post by goofyseeker3 »

that it seems like to be, that 80usd is with vat
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Re: stupid question: why cant you use internal rtc, by config?

Unread post by jca »

I wonder why there is such a difference. Thanks for the info: I looked at this type of board before but they seem to be in the $200.00 range but at $66.03 I don't think I can pass on it.
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limi
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Re: stupid question: why cant you use internal rtc, by config?

Unread post by limi »

Assuming you know about this? http://modernhackers.com/mister/ — has builds for various boards.

(Haven't tested any of these myself, so I don't know if they work)
goofyseeker3
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Re: stupid question: why cant you use internal rtc, by config?

Unread post by goofyseeker3 »

also, 256MB sdr sdram chips are around under ten usd

i hope the main project will work directly on the SoCKit
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Re: stupid question: why cant you use internal rtc, by config?

Unread post by jca »

limi wrote: Tue Dec 29, 2020 9:43 pm Assuming you know about this? http://modernhackers.com/mister/ — has builds for various boards.

(Haven't tested any of these myself, so I don't know if they work)
Yes, the link was posted recently. I did not pay too much attention to the Arrow but noticed that the DE0 nano SOC was not mentioned.
I already have MISTer and have been very pleased with it. The Arrow would be to really learn HDL, I have several small boards which I used but the Arrow is a lot better with all these built in peripheral. With my other boards I use small perfboards -> rat nest and where I live nothing is available so ordering some components, connectors, .. here and there can become expensive as shipping to Curacao is not cheap and on top of that everything is taxed (duty, sales tax). With the Arrow there is more than enough peripherals to play with, the FPGA itself is overkill for what I am able to do at the moment but will permit to test the MISTer port, after adding some memory.
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Re: Stupid Question: Why can't you use internal rtc, by config?

Unread post by jca »

I bit the bullet; I could not let it pass at this price. And indeed it is the Terasic board which is almost 6 times more expensive. Some magic is going on here.
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