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GokMasE wrote:spiny wrote:If I remember, I'll take some pics if it actually fitted later on this evening.
Please do, that would certainly be of interest
spiny wrote:Fujiyama wrote:spiny wrote:I used a DS1338 with my Monster board OK, but I did need to add two resistors, in order for it to read the time correctly:
viewtopic.php?f=15&t=27627&hilit=rtc+dallas+monster&start=450#p307565
I bought a cheapo eBay (probably fake, but OK for testing) Chronodot 2, based on the DS3231 which I haven't tried out with the MonSTer yet. The wiring info is in the MonSTer thread somewhere, isn't it?
Please tell more about those resistors -values and where you connected them?
the info is in the thread I linked to.
joska wrote:Fujiyama wrote:Does the need for the Y2K fix or not apply for all sorts of clocks in a plain ST/STe (internal clock boards, RTC modules attached to the MonSTer, clock cartridges etc.)?
The Y2K-fix applies to all ST's that does not have the Mega/MegaSTE/Stacy RTC. However, if you use a third party RTC and some autofolder utility to update GEMDOS time from this, TOS 1 usually does not need to be patched (depending on how the RTC software works). In this case only TOS 2.x is affected on these machines.Fujiyama wrote:I guess I'm wondering how the computer knows if it should use the keyboard processor or whatever else the Mega STe/STacy/Mega ST uses?
TOS from 1.02 and upwards will attempt to access the Mega/MegaSTE/Stacy RTC when booting. If the RTC responds, TOS will read the RTC and update the GEMDOS internal clock (a pure software clock running off the 200Hz timer interrupt) with the RTC time/date. From then on GEMDOS will only refer to this software clock, not the RTC.
If the RTC does not respond TOS reads the time/date from the keyboard processor and sets the GEMDOS time to this. A warm reset does not reset the keyboard clock so you don't have to set the time/date after a warm reset.
The original Atari RTC (or keyboard clock if no RTC is present) is only accessed by TOS in these cases:
1. When booting the GEMDOS clock is updated with RTC time/date.
2. When the XBIOS Settime/Setdate functions are called. These are the interface to the RTC hardware, used to change RTC time/date.
3. In TOS 2 the RTC will be updated also when the GEMDOS time/date is changed using the GEMDOS Tsettime/Tsetdate calls. TOS then reads back the time from the RTC and updates it's internal GEMDOS clock according to this. This does not happen in TOS 1.
(3) is important, and the reason why TOS 2 needs to be patched when using an aftermarket RTC. The RTC software reads time/date from this custom RTC, and sets GEMDOS time accordingly using Tsettime/Tsetdate. Because there is no stock RTC, TOS falls back to the keyboard clock and when reading back the year the year is wrong. On a Mega/MegaSTE this is not a problem, because the keyboard clock is never used by TOS in this case.
So why is the keyboard clock year wrong? Because GEMDOS year 0 is actually 1980, while keyboard clock year is the last two digits of the actual year. So GEMDOS year 10 is displayed as 1990, and inside the keyboard clock it's stored as 90. This means that when TOS updates the keyboard clock, it actually writes GEMDOS year + 80, and when reading keyboard clock it reads keyboard year - 80.
Now, this is no problem when year is between 1980 and 1999. But try to do this math with a year after 2000, and you'll see that this does not add up
It is not a problem with the original RTC, because RTC year 0 is also 1980 so no conversion is needed between RTC and GEMDOS time.So to sum up this rather confusing post - when using a MonSTer RTC and the M_RTC.PRG utility the Y2K fix is only needed on machines with TOS 2 and no original Atari RTC. I don't know if MagiC is affected. EmuTOS is not.
Fujiyama wrote:My big question is how TOS "knows" if a clock was factory fitted by Atari as part of the motherboard design (e.g. my Mega STe) or if an after-market third party clock board (as in my STe where I've placed a battery-backed clock between one of the TOS EPROM sockets and the EPROM itself)?
Fujiyama wrote:Is the difference (between needing a Y2K fix patch or not) really if the computer has no clock at all or if it has a hardware battery-backed clock (regardless of it being part of the Atari motherboard design or added as a 3rd party board later)? At least I get that the keyboard clock is the one causing problems (and thus needs a Y2K fix of some kind), but I don't get why TOS falls back to this keyboard clock when in fact the computer has a battery backed hardware clock already (my STe with the clock board in the TOS socket).
Fujiyama wrote:I haven't tried it yet, but from this posting of yours it appears I first need to read the TOS EPROMs (in order to get a TOS dump), then run the TOSdump file through the Y2K patcher to have it create a new, Y2K patched TOSdump file which can be used for burning new TOS EPROMs or flash the MonSTer board, correct?
Fujiyama wrote:From then on I assume it's just a matter of setting the time any way you like such as through the Xcontrol control panel accessory?
Fujiyama wrote:I know several Atari users who don't have MonSTer boards (some without hard drives even) -do you have a similar patcher which can be put in the AUTO folder?
joska wrote:Fujiyama wrote:I know several Atari users who don't have MonSTer boards (some without hard drives even) -do you have a similar patcher which can be put in the AUTO folder?
The nature of this patch is to modify the TOS binary itself. So if anybody wants to use this patch but not flash/burn it to a TOS ROM, they would have to load and run the patched TOS with SELTOS.
spiny wrote:I'm not using any kind of patched TOS, I'm just using the clock set PRG from Alan, which I have put ion the AUTO folder of my hard drive.
Fujiyama wrote:spiny wrote:I'm not using any kind of patched TOS, I'm just using the clock set PRG from Alan, which I have put ion the AUTO folder of my hard drive.
What kind of Atari are you using?
You mean the RTC software found on the MonSTer ordering/info page?
So you're saying that by putting it in the AUTO folder it does the Y2K fix upon booting so you don't have to re-enter the current date/time?
Fujiyama wrote:
Back to the pullup resistors I looked up several sites where several of them mentioned 10K, likewise the DS3231 "Chronodot" RTC module's own site where it says "Since many devices that have I2C buses already have the resistors in place, these are not provided with the ChronoDot. But there are two locations for 4.7K or 10K resistors to be soldered, in case your controlling device does not have its own pullup resistors" so I went for two 10K resistors as Alanh suggested.
For some reason though the time isn't kept after powering off the computer, then on again later. The battery is brand new and all the connections are good.
spiny wrote:Fujiyama wrote:What kind of Atari are you using?
You mean the RTC software found on the MonSTer ordering/info page?
So you're saying that by putting it in the AUTO folder it does the Y2K fix upon booting so you don't have to re-enter the current date/time?
in a word, yesthe software sets the clock properly, when i save files the date and year are correct.
I'm using an STM for this one, but I see no reason that it won't also work on an STe.
Fujiyama wrote:For some reason though the time isn't kept after powering off the computer, then on again later. The battery is brand new and all the connections are good.
do you mean the time is not read correctly, or that the time on the RTC itself is resetting to some default value ?
spiny wrote:just to confirm, this is how I have wired the resistors on my setup. I used 1k, as that was all I had at the time, but they seem to work and the clock and clock software are working.
rtc.png
Fujiyama wrote:
Is it correct to assume that the clock hardware isn't (usually) the source of the Y2K problems but just the keyboard clock limitation, so additional software is needed to translate and fix this for TOS to be able to use?
Fujiyama wrote:I'm going to continue testing by having the Mega STe turned off for extended periods of time then power up again and see, but that program in the AUTO folder seems to do the trick.
Fujiyama wrote:When I get my STe out (currently without a MonSTer board) which has a clock board (a small circuit board with a battery in between one of the TOS EPROMs and its IC socket) it'll be interesting to see if the same Monster RTC software will act as a Y2K fix.
spiny wrote:just to confirm, this is how I have wired the resistors on my setup. I used 1k, as that was all I had at the time, but they seem to work and the clock and clock software are working.
rtc.png
GokMasE wrote:This is my take on adding the needed resistors:
(There wasn't much space, so had to use both sides of the board to make the resistors fit)
Hopefully I got it right, at least nothing has been shortened
Regards,
/Joakim
joska wrote:Fujiyama wrote:I'm going to continue testing by having the Mega STe turned off for extended periods of time then power up again and see, but that program in the AUTO folder seems to do the trick.
That's because without this program in the auto-folder the MonSTEr RTC is never used... But I don't understand why you would want to use a retrofitted RTC in your Mega STE? It has it's own RTC, adding another RTC does only one thing - complicate stuff.
Fujiyama wrote:When I get my STe out (currently without a MonSTer board) which has a clock board (a small circuit board with a battery in between one of the TOS EPROMs and its IC socket) it'll be interesting to see if the same Monster RTC software will act as a Y2K fix.
TOS does not know ANY OTHER RTC than the original, factory fitted RTC you'll find in the Mega, Mega STE and Stacy. Is the retrofitted RTC in your STE of this type, or does that STE have any other OS than TOS 2.0x? If yes to either of these questions, then you have no Y2K problem on that machine. Don't do anything, just set time/date with the Control Panel and leave it alone. Oh, and make sure that the battery is OK.
If it's NOT of the same type as the original, factory fitted Mega/Stacy RTC you'll need the driver for this RTC to be able to use it. Depending on the RTC and the driver this may or may not handle the Y2K bug. But unless the RTC driver (not the MonSTer RTC driver, but the driver for the particular RTC in that particular machine) hacks around the Y2K-bug somehow you WILL need a patched TOS or other Y2K-fix to avoid the Y2K-bug.
The only reason why the MonSTer RTC driver fixed the time/date-problem on your Mega STE is that you probably don't have a battery for the original, factory-fitted RTC, and when the MonSTer RTC driver was installed the MonSTer RTC was actually being read. The MonSTer RTC driver is NOT a Y2K-fix at all, and I can assure you that it will have no other effect than slowing down boot on any machine that does not have a MonSTer and a DS1338-compatible RTC connected to the MonSTer.
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