RTC guide?

Current solutions and designs.
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Bikerbob
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Re: RTC guide?

Post by Bikerbob » Mon Nov 18, 2019 4:08 am

Ok, just ran into something else.

I have a few computers with TOS switchers. One on an STE exxos that gives me 2.06

Also on on my MEGA ST - Wizztronics compatability plus II (NEED DOCS IF ANYONE HAS THEM!!) which also gives 2.06

BUT on both machines when booting date year goes to 28

I thought that 2.06 was supposed to fix this?

James

tzok
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Re: RTC guide?

Post by tzok » Mon Nov 18, 2019 9:03 pm

It is not up to TOS to fix this. This is a flaw in the original IKBD firmware (actually it is projected behavior). TOS uses GEMDOS clock, but every TOS since 1.02 polls the IKBD RTC (via XBIOS's Getttime()) every time GEMDOS's Tgetdate() or Tgettime() is called. And same with Tsetdate()/Tsettime() (via XBIOS Settime()). On TOS 1.00 IKBD/XBIOS clock and GEMDOS clock were kind of independent. But since 1.02 they are sync'd together. IKBD firmware rejects anything higher than 0x99, and returns 28 when reading uninitialized field (actually it is 128 in pseudo-BCD: 0xC8). Nevertheless GEMDOS accepts 0xB8 as a correct year, as it would accept any year from 0x00 (1900) to 0xF9 (2059) or even 0xFF (2065), despite the BCD format requirement.

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Bikerbob
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Re: RTC guide?

Post by Bikerbob » Tue Nov 19, 2019 6:00 pm

So Ppera improved TOS is supposed to fix this.. so then he is not polling the IKBD anymore then it would seem.

SO if this is common through all TOS why is there not a a common patch program that should work on all TOSs?

Sorry if this is a stupid question tzok.

James

tzok
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Re: RTC guide?

Post by tzok » Wed Nov 20, 2019 12:14 pm

I don't know what PPera has done, but I think he made an offset of 20 years between IKBD clock and GEMDOS clock. So XBIOS subtracts 20 years when setting the IKBD clock, and adds 20 years, when reading it.

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Bikerbob
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Re: RTC guide?

Post by Bikerbob » Sat Nov 30, 2019 3:14 pm

So my original posting in here was about the DeskCart!

Both of mine are working.. but I did find part of the issues.

The deskcart was fairly early 87 - it was designed before COPs or newer control panel and has no idea about CPXs

The cartridge and the clock routine are loaded by an .acc not an Auto program. The DeskCart sits as one of the ACC - within that acc program you can access all the cartridge functions. one of which is a QMI Control panel which replaces the standard Atari one.. in fact in my testing you have to remove the atari control panel or other extended control panels as they will conflict. I have gotten resets, corruption and crashes when trying.

ALSO it does accept 2019 as a date - it just uses it as 1919 - for the purpose of file dating.. thats fine. Day of the week is off. leap years would be off etc.. The battery replacement and the chip are keeping time great. I know Troed wrote a little program that would run in the autofolder that would then add so many years etc.. except in this case since it is called as an acc. it would just have to be manually run.

The kick is.. if I cannot modernize its running with newer control panels etc.. not sure this is worth the while, unless I was using the computer specifically for programming or something where the functions of Deskcart are super useful, but all the newer CPXs are not required. oh well.

James

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