Real Time Clock Board

[Bryce]

The 664 only scans for the first 8 ROMs (ROM 7 - 0). If the RTC ROM is in a slot above this, then it won't be visible or usable on a 64K CPC (the 6128 scans for ROMs 15 - 0). You also don't mention what was installed on the X-MEM. You may just have used up to much of the internal 664 RAM because of too many ROMs being installed. This can effect many games.

Bryce.

[Poliander]

Thank you for your response! IIRC (currently at work) but ROMs in use are...

#00h - BASIC (not in use)
#01h - FW 3.15
#02h - RTC
#07h - CP/M

BTW on the 664 the RTC works even when I place it's ROM in X-MEM between 08h - 0Fh (but the game quits immediately after start displaying I have to reboot the machine). I used the same ROM configuration for both testing with 664 and 6128.

[TotO]

If FW3.15 is used, the 664 will scan for 16 (FW315EN16) or 32 ROMs (FW315EN32) not 8.

[dxs]

- CPC 664 + CPC-RTC w/o X-MEM = RTC is not available at all (not shown on boot message)

Do you confirm his behaviour? Do you have anything else connected to the 664? Is your expansion connector spotless clean? Are the 3 jumpers of the RTC in the "Int" position when NOT using the X-MEM?


Unfortunately I couldn't test the RTC with a 664 because I don't own any. Anyone having a 664 and the RTC board could confirm that the RTC works (or not) on 664?
If not, can you try replacing the lower ROM (using X-MEM or lower rom board from Bryce) with a 6128 firmware? Also try replacing rom 0 (basic) with a 6128 version?

---------------------------------------

#00h - BASIC (not in use)
#01h - FW 3.15
#02h - RTC
#07h - CP/M

I'm using this opportunity to remember users that under no circonstance should the jumpers be set to "INT" when using an external romboard, be it the X-MEM, Megaflash or any other ROM board (at least one being based on modern chips, not an old one where you physically plug EPROMS).

[Poliander]

Do you have anything else connected to the 664? Is your expansion connector spotless clean? Are the 3 jumpers of the RTC in the "Int" position when NOT using the X-MEM?

There was nothing else connected and I confirm the jumpers were set correctly (I was absolutely aware that this is required). The expansion connector works perfectly when using it together with X-Mother/X-Mem and I used the same cable/plug when trying without X-Mother/X-Mem, directly connected to the RTC. Unfortunately I have no other ROM board to test with.

Could someone connect the RTC to a plain, unmodified 6128, without any other hardware, and try to start Fruity Frank, please? I suspect there is a collision in memory use somewhere which also affects my 664 setup.

[dxs]

Thanks for quick reply! I'm on holiday for a few days more so I can't test that for you now unfortunately.
Maybe can you try another version of the game (cracked / repacked / trained...).


I'm more concerned about possible incompatibility with the 664, which is quite strange as the RTC does work with both 464 and 6128. 664 and CPC RTC owners see above posts for requested help please!

[Poliander]

I did just some testing again. And I have to tell you, this time the RTC works "as usual" on my CPC 664 when directly connected, without X-MEM. (I could think of one jumper did not properly fit...) So X-MEM can be fully dismissed from my "testing matrix" :-) ...and leaves an incompatibility between RTC and at least one game on both machines, 664 and 6128.

[arnoldemu]

I did just some testing again. And I have to tell you, this time the RTC works "as usual" on my CPC 664 when directly connected, without X-MEM. (I could think of one jumper did not properly fit...) So X-MEM can be fully dismissed from my "testing matrix" :-) ...and leaves an incompatibility between RTC and at least one game on both machines, 664 and 6128.

Are you excluding the RTC ROM software from this test?

So is the bug with RTC on it's own ?

EDIT: I am wondering if the RTC ROM has installed a firmware interrupt. Fruity Frank uses firmware. Maybe it needs to reset the firmware to run correctly?
EDIT: Does Donkey Kong (ocean) also crash?

[dxs]

Ok for the 664, a jumper is indeed the most likely cause.


But you said everything is working fine with 6128 + RTC - XMEM.
The fact is that from the computer's point of view, regarding RTC operation, there is very little difference between this config and 6128 + RTC + XMEM.


So maybe you should try removing other ROMs from XMEM like fw3.15...
Also try the game with this config: 6128 + XMEM - RTC , both with or without the RTC rom, but with module physically unplugged.

[Poliander]

@dxs X-MEM can be excluded, same effect both with and without X-MEM (I updated my original post accordingly)
@arnoldemu Donkey Kong runs fine on both 664 and 6128 (tested w/o X-MEM)

[dxs]

Ok I'll make some tests when back home. I think that the function which displays real time (ctrl + esc) or the programmable timer could be the culprit. I'll also check the one other known trouble soft aka  hxc manager. If possible I'll release a patch but I'm quite ASM-impaired 🙄

[TFM]

Ok, there was not 664 to use. But I could do a test with the regular CPC6128.


On an MX4 board I had the dxs RTC, the X-MEM, X-MASS and Albireo. The RTC jumpers were all set to ext (see handbook).
I started Fruity Frank and it worked without an problem.


Therefore the RTC is not the problem, it could be the TimeROM on 664, but I don't have a 664 here.

[Poliander]

Thanks for testing. But I experience same problem on both my 664 and 6128.

[1024MAK]

Yay, my RTC arrived yesterday 

I'm at work again until very late today  . So I will play with it at the weekend.

Thank you very much @dxs 

Mark

[TFM]

In addition I tested Fruity Frank on my CPC6128 yesterday with only RTC connected and the TimeROM enabled. Everything worked fine. Couldn't reproduce the error you saw.
@Poliander: Sorry, can't help you any further (maybe try another PSU).

Something else:
However I saw that the TimeROM-ROM (located a postion 9 in an X-MEM) does not find the RTC when the RTC is at ROM select &72 (jumpers set to EXT), but FutureOS does find the RTC and shows time and date correct. So maybe the Time-ROM is not scanning all ROM slots for the RTC. I have to look into this one day.

[netmercer]

Something else:
However I saw that the TimeROM-ROM (located a postion 9 in an X-MEM) does not find the RTC when the RTC is at ROM select &72 (jumpers set to EXT), but FutureOS does find the RTC and shows time and date correct. So maybe the Time-ROM is not scanning all ROM slots for the RTC. I have to look into this one day.

Hi,
@TFM
use the TIMEROM File dxs delivered to you per e-Mail, not a copy of the ROM from RTC board.

Kind Regards
netmercer

[TFM]

@TFM
use the TIMEROM File dxs delivered to you per e-Mail, not a copy of the ROM from RTC board.
Kind Regards
netmercer

Good advice, can you post it here? (I had an email crash).

[netmercer]

Good advice, can you post it here? (I had an email crash).

Hi TFM,
it had been already posted at the first side of this thread 

[TFM]

Hi TFM,
it had been already posted at the first side of this thread 

Yes, but that's 1.00 and not 1.01

[netmercer]

Yes, but that's 1.00 and not 1.01

Yes, that's 1.00 from 19/05/2015, which I'm using too. I don't know a version 1.01 of CPCRTCEN.ROM.

[TFM]

Yes, that's 1.00 from 19/05/2015, which I'm using too. I don't know a version 1.01 of CPCRTCEN.ROM.

Maybe I mix things up, will take a look later. 

[dxs]

You are both right.

1.01 is for onboard EPROM only
1.00 is for external romboard


The difference is that the onboard version searches for the RTC module at position 2, since it is hardwired that way. The External version starts looking at &72. Reason for that is that using onboard EPROM there would have been a slight delay at bootup while searching through &72 down to &2.
Hence V1.01 won't work when used in X-MEM with jumpers to "EXT".


In this thread (first post, or as I sent via email) you will only find v1.00, as users weren't supposed to dump the EPROM I shipped 
The numbering was used to make sure there was no mixup during development.

[TFM]

Let me ask an illegal question: The onboard EPROM is an 27C512 (iirc), that's 32 KB, the time-ROM uses 16 KB. Are the other 16 KB are mapped in somewhere? Is it for future expansion?


A mystery of the clock! 

[dxs]

Actually the 27C512 is 64KB.
The remaining space isn't available, I chose this IC beacuse this was the least expensive memory I could have! The board is compatible with 27c128 27c256 27c512 I fixed the unused address pins at GND or 5v to ensure compatibility.

Let me ask an illegal question: The onboard EPROM is an 27C512 (iirc), that's 32 KB, the time-ROM uses 16 KB. Are the other 16 KB are mapped in somewhere? Is it for future expansion?A mystery of the clock! 

are you expecting users to reverse-engineer FutureOS ? 

[TFM]

Isn't it crazy? 16 KB are more expansive than 64 KB.    But yes, you could fit FutureOS on it.