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General Category => NC100, NC200, PCW, PDA600 - the rest of the Family! => Topic started by: JonB on 23:24, 01 October 19

Title: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 23:24, 01 October 19
Hi all

Following discussion of a real time clock board for the PCW, I'm pleased to announce that work on the hardware design and software utility is now complete.

The documentation is available on the Wiki: http://www.cpcwiki.eu/index.php/URTC-8_Universal_RTC_for_Z80_computers

The basic price for the board, fully built and tested, is £37 plus shipping. Please read the wiki page to find out more.

At this time there is only a limited number of boards, but I can acquire more if the demand is there. Please let me know if you want one, and I will maintain a list. If you have uIDE-8 on your computer, you will need to add a third 40 way connector to your Z80 bus cable, if there isn't one there already. Orient it the same way round as the one your uIDE-8 is plugged into. If you don't have uIDE-8, you will need either a Z80 shim or PCW expansion board, plus a Z80 bus cable in addition to the uRTC board. See the uIDE wiki page for details of how to connect uRTC to the computer, and pretend that it is talking about uRTC rather than uIDE!

Thanks
JonB
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 16:07, 02 October 19
Demo video on the PCW (when it completes upload & processing):

https://youtu.be/CDJlPLYHUEA
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: LambdaMikel on 20:52, 02 October 19
Nice! Now I need to get a PCW...
would it work with the CPC as well somehow?
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 22:01, 02 October 19
Not the 6128 as it uses 16 bit I/O addressing. 464 I’m not sure about.
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: GUNHED on 00:08, 03 October 19
Not the 6128 as it uses 16 bit I/O addressing. 464 I’m not sure about.
It's 16 bit for all CPCs, Plus and GX4000. But for CPC there are about five other solutions (regarding RTCs).
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 10:46, 03 October 19
Good to know, thanks Gunhed.

So, no uRTC-16 then....
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: torrind on 21:20, 04 October 19
Me Please Jon !


Darren
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: sucram on 12:06, 07 October 19
I'm interested in the URTC-8.
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: TynH on 15:44, 07 October 19
I’ll have one as well please. Even though I literally have no time whatsoever right now, which seems slightly ironic.  ;D
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 18:19, 09 October 19
OK, I've built four units and will contact @GeoffB17 (http://www.cpcwiki.eu/forum/index.php?action=profile;u=1489), @torrind (http://www.cpcwiki.eu/forum/index.php?action=profile;u=2864), @TynH (http://www.cpcwiki.eu/forum/index.php?action=profile;u=3010) and @Proteus (http://www.cpcwiki.eu/forum/index.php?action=profile;u=464) for payment soon. I did have a fifth unit but one of the clock chips I bought was dead, so I have to wait for more to arrive before sending out any more. @Sucram, you're next.

Oh.. I found another bug in the uRTC.COM program, which I thought I'd squashed.. sigh.

By the way, I dropped the price to £34 plus shipping.   ;D
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 14:45, 10 October 19
OK, I have fixed the bugs in uRTC.COM and will now ship the boards.

The wiki page has been updated with a download link. You want the latest for the PCW, which is (as of this post) v0.2.
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: torrind on 20:41, 15 October 19
Hi Jon,


This is how everything is connected.


Regards,


Darren
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 22:30, 15 October 19
[Context: Darren's having problems with his uRTC board...]

Hi Darren

As you know, I test every board before shipping in order to minimise the chance of problems when it is first used by the recipient.

The program (uRTC.COM) is waiting for the clock chip to deassert BUSY. If the chip is broken or not connected, this never happens, so the program is designed to time out and give the error message you are seeing. So either you have a bad connection or a defective LS668 or clock chip.

Please try the following in order to narrow it down.


If none of these actions get your uRTC working, then I would conclude the clock chip has developed a fault. I don't know how this could have happened in transit, unless you have inadvertently connected the board while the PCW was switched on (which I doubt - I'm sure you know what you're about!). I am waiting for some more clock chips from China so I can send you another one when they arrive.

There is another thing to try. If you have the program SURVEY.COM, please run it and tell me what it says (with the uRTC connected, and again with it disconnected). Also try IOMAP.COM, both are in the attached ZIP file. Are you running on a 9512 or 8256/8512 series PCW? It occurred to me that the uRTC I/O addresses may be already in use on the 9512. As I have no more clock chips I cannot test on my 9512 at the moment.

[Edit: I ran SURVEY.COM on my 9512 and it looks like the default uRTC I/O addresses (B0h to BFh) are free, so that's not the problem.]

Cheers
JonB
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: torrind on 01:31, 16 October 19
Hi Jon,

Thanks for the comprehensive response. OK so lots of strange stuff going on....

This is what I did:

1. I checked my home-made IDE cable - I don't have a vice and so used a pair of pliers - But after various tests tonight I've concluded its not working correctly and so I've hidden it at the back of my odds n sods drawer - never to be used again! I have taken my known working IDE cable currently being used by uIDE and added a new female connector - this seems to give better results but still uRTC doesn't work (when I say better results, I mean that survey.com doesn't crash when uRTC and / or uRTC are attached!!)

2. I swapped over the LS668's but this didn't make a difference (in fact the chip from uRTC placed into uIDE caused the C: drive to perform random beeps and display garbled directory entries, so I swapped them back.

3. I ran survey.com and iomap.com before and after uRTC was attached. HOWEVER, after doing so I noticed that if I ran survey.com with uRTC attached, it gave a value of 140 ports active and 139 disconnected as per the screenshots - BUT if I then ran survey.com again and again with uRTC connected, the value dropped from 140 to 139....

all very odd....

For info, uRTC is set to 1011 (reading left to right) and I'm running a PCW8256 with a memory upgrade to 512k


Ultimately it may be down to bad cable crimping by me, so I have ordered a ready-made cable from Ebay which should arrive in the next few days.

I'll let you know ???


[Edit - screenshots too large, so will send them separately.]

Regards,

Darren
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: torrind on 01:36, 16 October 19
here are the remaining attachments - smaller in size....
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 11:36, 16 October 19
OK Darren, thanks. It's telling that none of the I/O ports used by uRTC are seen (B0-BF) in the IOMAP report.

You're right, the crimp connectors are difficult to use when all you have is pliers (ask me how I know...), plus the connector itself always gets scuffed up.

I use a mini vise - one of these: https://www.amazon.co.uk/STANLEY-MAXSTEEL-Multi-Angle-Vice/dp/B001HBS0I0 (https://www.amazon.co.uk/STANLEY-MAXSTEEL-Multi-Angle-Vice/dp/B001HBS0I0)

Very cheap, not very accurately made (the thread on mine seems to be slightly bent so the jaws wobble slightly as I tighten it) but for the money it's spot on. And very, very useful.
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: LambdaMikel on 18:47, 16 October 19
Do yourself a favor and get the real thing...


https://www.amazon.com/Eowpower-Crimp-Ribbon-Cable-Connectors/dp/B072MM8X7Y/ref=sr_1_1?keywords=Eowpower+IDC+Crimp+Tool+For+Flat+Ribbon+Cable+And+IDC+Connectors&qid=1571240805&sr=8-1 (https://www.amazon.com/Eowpower-Crimp-Ribbon-Cable-Connectors/dp/B072MM8X7Y/ref=sr_1_1?keywords=Eowpower+IDC+Crimp+Tool+For+Flat+Ribbon+Cable+And+IDC+Connectors&qid=1571240805&sr=8-1)


 ;)
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: torrind on 21:35, 16 October 19
ooooh!    ;D


[Edit:  Just placed an order for one......]
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: torrind on 15:10, 18 October 19
Just a note to say uRTC is live!!! ;D  - it was all down to DDCC (Darrens Dodgy Cable Crimping)

[Edit:  I cannot get INITDIR.COM to work. If I issue the command on any drive, it freezes the PCW and I have to do a hard reset. For info, I'm running CP/M+ version 1.7h
Any ideas please?]



Darren
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: GeoffB17 on 16:39, 19 October 19
Hello Darren,

I've got 1.7h somewhere, I'll have to try this.

However, some questions.

How long do you leave it before deciding that the machine is locked up, and what happens in the meantime?   Is there evidence of disk activity?  Please give a little (lot ?) more detail.

Which version of INITDIR are you using?  I assume there's a screen message as it loads/starts?   Or don't you even see that?

Which drive are you trying?   Are you trying to run the process on a uIDE drive?   There are a lot of files on some of JonB's drives, and the prog may need to do a lot of work.   When you say there was a problem for ANY drive, does that include the floppy drive, or M:?

Geoff
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: GeoffB17 on 19:35, 19 October 19
Since the above, I've found I had already created a boot disk for 1.7h.

I've booted my PCW, and tried a few things.

I've run INITDIR OK on both B: (floppy) and on drive P: (one of the uIDE drives, which was empty anyway).   Both seemed to work fine, no hang up, lock, or whatever.   I notice that the INITDIR prog does not give any indic as to version, so maybe it's just a bog standard one, there is a date visible in the file of 15/12/82.  I think there is also a Y2K version of INITDIR?   More recent?

Or maybe the problem is nothing to do with the prog??

Geoff
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: torrind on 20:31, 19 October 19

Hi Geoff,


Thanks for the response.


Not sure of the version of INITDIR, but it was the version as pointed to by Jon here:


[size=78%]Download link (https://drive.google.com/open?id=1EJOk6i24IxBluL8gx61bsn-a5Gl5MGnY)[/size]


I've tried running it on the A: drive, B: drive and uIDE C: drive some of these drives have many files (c:) the B: drive only had two files on it.
After running the command, I've waited up to 10mins with no activity - my PCW hangs and I have to perform a hard reset. No errors are generated and no disk activity seen.
WRT the A: and B: drives, they aren't floppy drives, but Gotek drives. Not sure if this is the issue, however as you have got uIDE P: drive to work, and I can't, maybe its not that?


Darren
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: GeoffB17 on 21:16, 19 October 19
I've downloaded the version of INITDIR that you're trying to use.

I've put this file, and the one I've just used (that seems to work OK) onto my PC and used the FC (File Compare) utility to compare them both.

Your version seems to be maybe 1 byte bigger, there is an extra byte at &H35FF.   The two files are identical up to then, and seem to be identical after.   I don't know how the extra byte has got in, or if this is actually a problem, but my version works and yours seems NOT.

Quickest way to check this, I'll put the file I have into a .ZIP and attach it to a following message.   Try this and see what difference it makes.

Geoff
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: GeoffB17 on 21:22, 19 October 19
File attached.   This has been renamed as INITDIR.CPM by 22DISK, just rename it as .COM after extraction from ZIP.

This file is slightly larger due to junk on the end, the file has been copied by complete sectors, but this should not matter.

Geoff
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: GeoffB17 on 21:37, 19 October 19
Er - actually, it's the file I had that has an extra byte.   So the file you have seems to have LOST a byte at offset &H35FE.

Worry more about what's what when we find if the file I've just sent you works now!!

Geoff
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: torrind on 21:45, 19 October 19
Thanks Geoff, your version worked!!


Top job as always.




Darren
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: GeoffB17 on 00:38, 20 October 19
Darren,

Thanks for the note.  Happy to be able to help.

I'd be interested to hear that the INITDIR works fine with the Gotek drives as well.  The computer should see the image EXACTLY as it would a real disk, so it OUGHT to be able to manipulate the directory section of the .DSK (or whatever) file exactly as it would an actual disk.   I assume the process accesses the disk sectors directly.

Don't forget that the uIDE drives will have capacity for 384 files (max, dep on file sizes and 'extents') instead of the original 512.   The use of SET applies drive by drive (and disk by disk) so there could be cases where it's better to NOT use INITDIR.

I'm not sure how Jon's file has lost a byte, but I think Jon uses RS232 data transfer to move files between CP/M and PC, so I guess that somewhere along the way he's transferred the INITDIR.COM file and the link has dropped a byte.   So everything after that point has been one byte out, which will seriously upset the program.  Might have done something much worse than merely lock up the computer??

Geoff
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: torrind on 00:57, 20 October 19
Thanks Geoff...


INITDIR appears to work perfectly with Gotek drives and I have successfully timestamped files added to both A: and B: drives.


As an aside, I can't do the C: drive as there isn't enough room (im guessing because of c0: c1: c2: etc etc) is there anyway of doing this other than removing all files from each drive?


Darren
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JohnElliott on 01:07, 20 October 19
CP/M time stamps occupy every fourth directory entry, so INITDIR won't work on a drive where over ¾ of the directory entries are in use. You'll need to move some files off until fewer than ¾ of the entries are in use - there is no way round that.

SHOW x: [DIR] gives the number of free directory entries

SHOW x: [DRIVE] gives the total number of directory entries.
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 17:29, 20 October 19
Just a note to say uRTC is live!!! ;D  - it was all down to DDCC (Darrens Dodgy Cable Crimping)

Phew!
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: GUNHED on 17:31, 20 October 19
Sorry guys, I kind of lost track... are they now available?

Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 18:28, 20 October 19
Yes, though I am now waiting for some more clock chips. So there will be a short delay if you want one.
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: GUNHED on 19:05, 21 October 19
Yes, though I am now waiting for some more clock chips. So there will be a short delay if you want one.
Well, I would like to take two of them. Doesn't matter if I need to wait. Maybe you can add two of the IDE adapters for the PcW too. Would save postage.  :)
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 20:15, 21 October 19
For sure. Fortunately I just got a new set of uIDE boards...

Do you need a DOM or adapter boards with them?
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: GUNHED on 20:21, 21 October 19
For sure. Fortunately I just got a new set of uIDE boards...

Do you need a DOM or adapter boards with them?


Actually, I would need two complete working sets (for a friend and me). Please PM me as soon as you have them ready for shipping. I'm looking forward to this since decades.  :)
Oh, and everything external if possible. If not then I don't mind taking an internal board(s).  :)
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 23:43, 21 October 19
I can build one external adapter at the moment. It’s the edge connectors, I have one left. Do you want the lite or video version? Refer to the wiki page for details.

Just to remind you, uIDE can’t boot the PCW yet. You boot using a floppy then everything runs from the DOM. You need CP/M Plus v1.15 or later. There’s an image download link on the wiki page.
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: GUNHED on 18:04, 22 October 19
Hi, the wiki page is huge. Lot's of work done. However from scratch I can't find the difference between light and video version. In case the video version has more features I'll go with the video version please.
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 21:23, 22 October 19
The difference is that the Video version incorporates a composite video connector, which you don't need unless your screen has failed.
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: GUNHED on 16:52, 23 October 19
Ah, thanks! That's a cool feature actually. Since the monitors are running well I would prefer the lite (non-video) version.  :)
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: torrind on 14:25, 07 November 19
Bad news All!

My uRTC has died. The first issue I experienced was the error as per the attached pic (Pic 1)

I used the uRTC command to put the date and time back to normal, typed 'DATE' again and all was fine. I rebooted and the same thing happened again. I then changed the date and time again and rebooted. Now I get "URTC timeout during read operation"

I had a spare RTC chip which I replaced but this didn't work. I also replaced my cable just in case and swapped over the 688N IC but no joy.

Pic 2 shows a survey dump -

Any ideas folks?

Thanks,

Darren
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 11:31, 08 November 19
Well the first thing I see is you are using an old version of URTC.COM with -tp argument - this had an option for the Superbrain (-ts) but I later separated them into two COM files. The earlier version also had a few bugs in its date derivation code. So if I were you I'd try the later version first. Oddly I didn't update the version number - still says v0.2 but the help message is different.

Second thing I see is a missing space in the uIDE XDRIVER signon prompt. I would not have released it like that (I'm a bit of a stickler for prettyness).

So I am wondering if your drive has got corrupted. uRTC is a dead simple design and there is very little that can go wrong. In fact, it is so simple that I didn't even bother prototyping it before sending it for board production.

Looking at your SURVEY.COM output, I see C0-C7 missing. uRTC uses C0-CF (thanks to Epson's chip interface) and so all of these should be listed as active. You've only got C8-CF showing and this suggests a problem with the connections to the clock chip. If you have a multimeter, please check the following connections for continuity:-

Clock chip pin 4 to CPU A0
Clock chip pin 5 to CPU A1
Clock chip pin 6 to CPU A2
Clock chip pin 7 to CPU A3

Or, if you have a logic probe, see if the clock chip pins are active by probing them for activity. If they are flashing then you know they are connected to the CPU.

Next, test the 668 in the same way. Pins 2, 4, 6 and 8 are A7-A4 respectively.

If those are OK, put the probe on the /CS0 pin of the clock chip (pin 2) and try to run uRTC (no arguments needed). If there is activity then you know the 668 is working and selecting the clock chip.

If all else fails you'll need a new clock chip. I do not know if they are known for fragility. If you want to send me one or more chips to try in one of my units, PM me.
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: torrind on 01:35, 09 November 19
Hi Jon,


Thanks for the comprehensive instructions - I started by updating the uIDE driver which has now sorted out the space issue. I'm sure I was using the newest uRTC driver but I downloaded it again with no success. How do I confirm that im using the newest version of this driver please?


Looking at the next set of tasks for checking the physical pins of the RTC IC, you mention checking chip pin 4 to CPU A0 first? Although I know where chip pin 4 is, I don't know where CPU A0 is. Can you advise as I'll also need to do the same with checking the 668 connections.


PS. my RTC IC has slightly different numbering on it to yours supplied on the uRTC = "RTC72421 B EPSON 1742C" although I don't think this is an issue.

<EDIT: I also created a brand new v1.12 image onto a spare DOM just incase of any corruption. This didn't change anything either.>



Regards,


Darren
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 11:59, 09 November 19
Hi Darren

Your RTC chip should be ok to use.

Google “Z80 pinout” to get a diagram of the processor with the pins labelled. When testing continuity do not have the computer switched on.

Issue the command “URTC -h” and tell me what it says.

Make sure you are using -t (not -tp) in your profile.sub.

Cheers
JonB
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: torrind on 01:17, 11 November 19
Hi Jon,


All working again!


Basically, I continuity tested the pins on the two IC's to the CPU pins as suggested and all tested fine except 668 pin 6 to CPU pin 6 - I checked the connection and realised this pin wasn't soldered on the uRTC. I soldered it and this then worked OK, however, the clock still couldn't be found.


I then changed the RTC chip to one of mine again and this didn't work, but I left it in.


Finally, whilst I had the iron out, I re-soldered all pins on both the 668 IC and the RTC IC. This cured the problem and everything worked again  ;D


The only issue I then had was that after issuing a date and time change to the uRTC, I noticed that the uRTC didn't increment the time, it stayed the same date and time as per my original values. To cure this, I put your original RTC IC back in - It seems that whilst similar, my RTC ICs don't work.


Anyway - All sorted. Thanks again for the help.


Darren
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 11:26, 11 November 19
Hang on a mo - are you saying I missed a pin when I soldered the socket in?  :doh:

If so, apologies for that! Not sure what was the problem with the other joints - I use good quality Kester 60/40 lead / tin solder with rosin core and I have a Hakko temperature controlled iron so I am surprised some of the joints were unreliable... again, sorry.
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 23:39, 27 November 19
Quick update on availability.

The next batch of clock chips still has not arrived, although the arrival estimate is not in the past yet so I cannot complain to the seller. I have ordered another batch from a different company (also Chinese) and hope to see them before the end of the year. As soon as I get them I'll be building more boards.

Thanks to all who are waiting for your patience!
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: GeoffB17 on 01:36, 28 November 19
Hello Jon,

Just a note to report that my uRTC is working fine, no problems.   I'm keeping an eye on timekeeping, and I've noticed almost no time slippage so far - maybe a few seconds over a month or so.

I've not yet done very much regarding setting up some disks to make full/proper use of the time settings, but it's just a matter of time.  Time to spend, that is.  Worth doing with some disks, maybe not so useful with others.

Thanks again.

Geoff
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 18:20, 10 December 19
I am still waiting for new clock chips, darn it.

In the meantime I made some uIDE boards which didn't work properly. After a lot of head scratching I discovered the problem - a sub standard batch of LS668 comparators which don't work properly when bombarded with valid IDE data reads. Changing these for another brand I have in my parts bin makes the uIDE work properly. Bit of a relief... however, this same batch is used in the uRTC board. So if you are experiencing intermittent problems try to swap out the larger chip.

As a side note, the conditions under which the uRTC registers are accessed are much less rigorous than the uIDE data read operation. This may be why it seems to be OK in the uRTC application, but not in uIDE.
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 13:49, 11 December 19
Typical - moan about late chips one day, then they turn up the next day!  :D

I'll be reaching out to everyone who has requested boards today. With luck you might get them by Christmas...

  [ You are not allowed to view attachments ]  
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: GUNHED on 13:56, 11 December 19
Wonderful! Please PM me your PayPal and the amount of cash I need to send.  :)
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: sucram on 21:40, 22 January 20
Hello Jon,

Now I have found the time to install the uRTC.
I'm excited. It works without any problems.  :D

Thank you very much for your work!

Marcus
Title: Re: Announce: uRTC-8 universal RTC for the PCW and other Z-80 computers
Post by: JonB on 13:39, 23 January 20
That's what I like to hear!  :D