Still possible to get Minerva ROM

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NormanDunbar
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Re: Still possible to get Minerva ROM

Post by NormanDunbar »

ruptor wrote:Why is an RTC useful on a stand alone computer? Is it so you know when to make a cup of tea? :)
Because, Winback! :D (Other hard disc backup applications are available of course!)

When I had my QL attached to a Miracle Systems Hard Drive, I wrote WinBack to check if the last modification date was more recent than the backup date -- both stored in the file header. If so, that file was selected for a backup, otherwise, it wasn't.

Also, when using make to build software, it needs to know which files are more recent than the executable and/or the object files that make up the executable. Having the date corectly set is most helpful in those cases.

There are also some "activity planners" software around, so they definitely need the date setting.


HTH

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Norm.


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Re: Still possible to get Minerva ROM

Post by Ruptor »

NormanDunbar wrote:Because, Winback! :D (Other hard disc backup applications are available of course!)
I didn't see any battery in the pictures & the green pot makes the RTC sound as real as a plastic apple. Wouldn't a software clock that you set at turn on do the same job?


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Re: Still possible to get Minerva ROM

Post by NormanDunbar »

In a word, yes. But if people are like me, they forget and mess things up. ;)

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Re: Still possible to get Minerva ROM

Post by Pr0f »

Ruptor wrote:
NormanDunbar wrote:Because, Winback! :D (Other hard disc backup applications are available of course!)
I didn't see any battery in the pictures & the green pot makes the RTC sound as real as a plastic apple. Wouldn't a software clock that you set at turn on do the same job?
the battery is connected by a pair of wires and is usually heat shrinked to prevent shorts

And setting the clock everytime you switch on - why would you put yourself through that!?


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Re: Still possible to get Minerva ROM

Post by Derek_Stewart »

Pr0f wrote:
Ruptor wrote:
NormanDunbar wrote:Because, Winback! :D (Other hard disc backup applications are available of course!)
I didn't see any battery in the pictures & the green pot makes the RTC sound as real as a plastic apple. Wouldn't a software clock that you set at turn on do the same job?
the battery is connected by a pair of wires and is usually heat shrinked to prevent shorts

And setting the clock everytime you switch on - why would you put yourself through that!?
Maybe he likes Plastic Apples...

The other problem with the Minerva RTC, was if you have a (Super) Gold Card, which also has a supposed crash proof clock, with battery back up, there is a clash with clock updates, one from the Minerva MKII and the other from the (Super) Gold Card.

Personally, I used the (Super) Gold Card Clock to update the QL Clock on power up.


Regards,

Derek
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Re: Still possible to get Minerva ROM

Post by Ruptor »

Pr0f wrote:
Ruptor wrote:the battery is connected by a pair of wires and is usually heat shrinked to prevent shorts
So if a PIC was used to replaced the 8049 utilisation of its onboard RTC facilities would be a good addition I think. :)


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Re: Still possible to get Minerva ROM

Post by Pr0f »

Except that QL time is taken from the 4 bytes of the seconds counter in the Zx8302 - and all the other RTC offerings in super gold card or the Minerva MKII with I2C clock chip just update that with their own time - so it comes back to the question - if you are going to replace both ZX8302 and IPC - then yes, but it tends to be the higher end pics - like PIC32 series that have on board RTC and separate low power oscillator circuit...

The whole point of those other designs is to keep the clock running when the QL is off, and for the clock not to be corrupted when the QL is reset / powered on - which tends to happen with the ZX8302 clock implementation - that was originally designed to be battery backed up - but the components to support that were not fitted to most QL boards and in later releases the pcb design changed to eliminate them


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Re: Still possible to get Minerva ROM

Post by Derek_Stewart »

Hi,

If the 8032 and 8049 are to be replaced by a PIC, how would you connect it the QL board, some double header socket arrangement of some kind. his looks hard to implement.


Regards,

Derek
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