So I've got a SYMBiFACE and it's great and all, but I have real problems getting it to connect properly. I have to wiggle the connector, turn on and see if it worked, repeat many times, etc. I've only managed to get it to actually boot symbos from ROM once, and it crashed shortly afterwards.
I think this is an issue with the edge style connector. Anyone else have the same problems? I've cleaned the contacts with q-tips etc and while it helped a bit it didn't make the problem go away.
Presumably it's not too hard to actually add centronics connectors to the CPC if you can find them - I note the holes seem to be present in the PCB at least. Has anyone done this, anyone know where I can find connectors?
Other suggestions? Cleaning tips?
Thanks as always ;)
Have you cleaned the contacts in the connector too?
If the PCB edge is really dirty, try using an Ink eraser to clean the contacts.
Bryce.
Next time I'm at the shop I'll grab one of those to try. You mean the ones with an ink eraser on one side and a pen on the other? (Basically bleach, aren't they?)
EDIT: No I didn't clean the contacts in the connector. I figured with it being new they weren't suspect. You think I should?
Yes, you should! Use Ethonol or Propanol, but no 'hard' stuff for cleaning. Repeat cleaning until you get no more dirt (= dark dust on Q-Tips) off.
Also take a look at a picture to be sure that you have connected the cable right around.
Try to disconnect any hard-disc to see if the power supply could cause problems.
And finally: Good luck!
(It's a great expansion and it works very reliable in my hands, but my CPC has Centronics connectors, no PCB blade).
Hi! I was having the same problem as you and decided to use a Schneider CPC with centronic interface. The change was successful.
In this post symbiface (http://www.cpcwiki.eu/forum/amstrad-cpc-hardware/symbiface/30/) was said that edge connector could not align always as it should and perhaps it is our problem .....
Before using the Schneider I was thinking about how to connect the CPC w/o an edge connector. I got one 464 from ebay with this mod at the printer port:
(http://farm9.staticflickr.com/8302/8027868074_9c4a6763bb.jpg) (http://www.flickr.com/photos/86293740@N05/8027868074/)
It could be an alternative if you don't find the centronics connector. Something like this:
(http://farm9.staticflickr.com/8178/8027867716_e889321692.jpg) (http://www.flickr.com/photos/86293740@N05/8027867716/)
but soldered.
Thanks' for sharing the pics. Nice idea.
IMHO the new batch of SF2's has no problems with the connectors, I stick with cleaning ;-)
Quote from: TFM/FS on 22:35, 01 February 13
Yes, you should! Use Ethonol or Propanol, but no 'hard' stuff for cleaning. Repeat cleaning until you get no more dirt (= dark dust on Q-Tips) off.
Also take a look at a picture to be sure that you have connected the cable right around.
Try to disconnect any hard-disc to see if the power supply could cause problems.
And finally: Good luck!
(It's a great expansion and it works very reliable in my hands, but my CPC has Centronics connectors, no PCB blade).
I will try this.
The cable is definitely the right way around - 90% of the time I get the colourful symbos boot instead of the standard basic bootup, but typing "|SYM" it wont boot to Symbos. I did get it to boot to symbos twice, once it crashed shortly after (screen corruption) and the other it only got halfway to showing the desktop. Normally it gives a "press play then any key" message, sometimes I get a black screen. If I try with holding the ctrl key down and resetting it normally just gives me a blue/red/yellow corrupted screen.
I don't have a HDD connected at present so that isn't the problem.
Quote from: Joss on 00:40, 02 February 13
Hi! I was having the same problem as you and decided to use a Schneider CPC with centronic interface. The change was successful.
In this post symbiface (http://www.cpcwiki.eu/forum/amstrad-cpc-hardware/symbiface/30/) was said that edge connector could not align always as it should and perhaps it is our problem .....
I'm honestly surprised that any expansions work well. Mind you, maybe I just have a cleaning issue. Also, I don't have any trouble with my external floppy.
Quote from: Joss on 00:40, 02 February 13
It could be an alternative if you don't find the centronics connector. Something like this:
(http://farm9.staticflickr.com/8178/8027867716_e889321692.jpg) (http://www.flickr.com/photos/86293740@N05/8027867716/)
but soldered.
That's AWESOME! I didn't think of it. And I have a few 50pin IDC SCSI cables I could use with it. If the cleaning doesn't work then I think I will go this route...
BTW, at least on my 6128 behind the edge connectors there are holes for, I presume, centronics connectors to be soldered. But this mod looks far easier (and maybe with adding centronics connectors you would need to remove part of the PCB where the edge connectors are for it to fit).
Well, your floppy works, but the SF2 doesn't! That's a first hint. Now I have two ideas... which may be both rubbish, but hey....
1. It's an issue with the connector. Can you compare the connector of the DDI-1 floppy and the SF2? Do they look similar? Sorry, I mean the exact spacing of the pins.
2. Have you tried to install other ROMs like Maxam or Protext into the SF2? Do they work?
I was getting a couple of SCSI cables from ebay (http://www.ebay.de/itm/310161762238?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649#ht_3106wt_907) for a nice price, just for the future ;)
As I see, the pcb side of the edge connections from 464/664/6128 have a hole/line between the connections but not in the middle. Perhaps it helped not only to find the right orientation of the cable but too to have the connections at the right positions.
Quote from: TFM/FS on 19:51, 02 February 13
Well, your floppy works, but the SF2 doesn't! That's a first hint. Now I have two ideas... which may be both rubbish, but hey....
1. It's an issue with the connector. Can you compare the connector of the DDI-1 floppy and the SF2? Do they look similar? Sorry, I mean the exact spacing of the pins.
2. Have you tried to install other ROMs like Maxam or Protext into the SF2? Do they work?
I have a 6128 - so I use a 3.5" floppy on the second floppy connector. I also have a 464, but I haven't tried it with the symbiface, I don't have it with me right now though (and it is quite broken, well at least the case is trashed and the tape player destroyed - it ought to work for connecting a symbiface though).
I haven't tried installing any other ROMs, maybe I should do this...
Quote from: Joss on 20:33, 02 February 13
I was getting a couple of SCSI cables from ebay (http://www.ebay.de/itm/310161762238?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649#ht_3106wt_907) for a nice price, just for the future ;)
As I see, the pcb side of the edge connections from 464/664/6128 have a hole/line between the connections but not in the middle. Perhaps it helped not only to find the right orientation of the cable but too to have the connections at the right positions.
I'm not sure I follow what you mean... you mean where the slot is for getting correct orientation? The connector is pretty tight, I don't think it can move sideways really at all - I tried this in case it was somehow misaligned.
Tomorrow I'm going to get some ethanol and try cleaning it better.
Quote from: Joss on 00:40, 02 February 13
It could be an alternative if you don't find the centronics connector. Something like this:
(http://farm9.staticflickr.com/8178/8027867716_e889321692.jpg) (http://farm9.staticflickr.com/8178/8027867716_e889321692.jpg)
but soldered.
I have this mod on my 464. It's the most reliable connection you can have and the connection
cables are simple.
Bryce.
Quote from: Munchausen on 22:26, 02 February 13
I haven't tried installing any other ROMs, maybe I should do this...
Well, you can try my ROManager and install a ROM, to see if it works. If other ROMs work then maybe the Symbos ROMs may have some bits changed. Just an idea. (Hey, I'm not telling you to install FutureOS and check if it works, but you could ;-))
Quote from: Munchausen on 22:29, 02 February 13
I'm not sure I follow what you mean... you mean where the slot is for getting correct orientation? The connector is pretty tight, I don't think it can move sideways really at all - I tried this in case it was somehow misaligned.
you got what I meant :)
Ok, this is driving me insane! I've been very busy and didn't have time to try again until now, but I've just spent some time soldering IDC pin headers to the CPC, and it has made absolutely no difference.
Here's what happens on boot (correct, I think):
[attach=2]
Here's what happens if I hold down control to try and get it to boot Symbos after boot (it first displays "booting symbos..."):
[attach=3]
And here's what happens if I try to boot symbos from floppy drive with the symbiface connected:
[attach=4]
If I try to boot by typing "|SYM" or "|SYMBOS" it just says "Press play then any key".
I also tried disabling all the ROMs with the jumper and booting from floppy - it made no difference.
Does anyone have any clues? I'm now using a very short cable between the symbiface and EXT port. Could it be power supply related (I'm powering everything from one of those external hard drive power adapters with a molex connector - the SYMBiFACE is connected to the 12V and the 6128 5V)?
I really don't know what to do next. :'(
My bet is on a bad connection on one of the address lines, probably to the SymbiFaces RAM IC. Have you tried removing and re-seating the ICs? You'll have to re-install SymBOS on the RAM afterwards of course.
Bryce.
That does sound like it's on the right lines (heh, a pun), but the RAM is not socketed.. the CPLDs, RTC and AVR micro (PS/2 controller) are though.
Do you think I should try re-seating the CPLDs? They're some sort of QFP package though and I'm not certain about removing them without damaging the socket. Also, you think it'll be ok to remove them with the RAM battery connected?
What else could it be... the only other thing I can think of is a dry joint (which seems unlikely)?
Thanks!
I just tried the symbiface with my 464 and nothing happens at all there... it just boots as normal. However, I haven't soldered IDC headers so it could be that the connection is bad. I'll solder some tomorrow and see what happens, but not holding out much hope.
Have you installed Amsdos on ROM 7 ? Stupid quesiton, I know, but have not other idea? (Don't know it you need it for Symbos, but I guess 'press play' does maybe indicate that.
Are the ROMs ok, or are there some bits corrupted?
So I don't have the AMSDOS rom installed in ROM 7... maybe that is why it does nothing on the 464? But it shouldn't matter for the 6128 because I just leave ROM 7 disabled. BTW, is it rom 7 or rom 8? The switches go from 1 to 8, so I thought it is the 8th switch right?
I can't run the rom manager right now because I have no way to make floppy disks (I'm living at my girlfriends now and my desktop is at my place). But next weekend I am going back, so I'll try to make some disks when I do, and try running some things (FutureOS, ROM manager, etc)
I will also try to find another way to power the SYMBiFACE, in case that is the problem.
Also, I guess the ROMs are not corrupt, but how can I know for sure?!
I don't have a hard drive connected, but from what I understand that shouldn't be a problem.
So the 464 doesn't show anything on boot because it doesn't initialise ROMs past 7. Is there a way I can do this manually? As far as I can tell I need to manually poke some values into registers and then call an intialisation routine... but I'm having trouble figuring out how to do it. Otherwise I'm stuck with the 464 because the tape drive is broken so I can't load anything...
Ok, so after looking here (http://www.cpcwiki.eu/forum/programming/understanding-booster-rom/) I guess this isn't easily possible without loading some software to do it. So I won't really be able to test this with the 464...
Quote from: Munchausen on 10:55, 21 April 13
So I don't have the AMSDOS rom installed in ROM 7... maybe that is why it does nothing on the 464? But it shouldn't matter for the 6128 because I just leave ROM 7 disabled. BTW, is it rom 7 or rom 8? The switches go from 1 to 8, so I thought it is the 8th switch right?
That's right. Since it's ROM 7 when starting at ROM 0.
I haven't been able to do much testing of this; I needed to make disks with the rom manager and some other roms - the MAXAM assembler ROM for example would be good, because it does a checksum of itself. But I have no way to make floppy disks at the moment, as I'm away from home until July so I don't have any PC with floppy drive to make discs with - I brought an old laptop with floppy drive with me just for making disks, but it turns out the machine is irrevocably deceased.
However, a couple of days ago I got some goodies in the post from Bryce :D This included the LowerROM. And after testing just now, my CPC will not boot with FW3.1 on the LowerROM - it never finishes booting, or cycles infinitely. Since Bryce tested the LowerROM before sending it to me, this means that there almost certainly is a bad connection somewhere (be it cable, connector, or in the CPC itself), if my thinking is right? This is actually a really good and somewhat relieving result for me - as more than likely my Symbiface is working but I have a connection problem.
Tomorrow I will check the signal lines with a multimeter and resolder as necessary (the IDC pin header I added could be bad). Hopefully I can get everything working and be good to go - fingers crossed anyway!
If the LowerROM is cycling, I'd say you have a Data line not getting through. Check all the connections again. Judging by the description of what you were getting on the SF2 my money is on D2.
Bryce.
Is it the fixed version of Firmware 3.1 (i.e 3.12)...?
The old version could cause a boot cycle error on a real CPC.
Arg! Well, I'm pretty sure it's a connection problem. I've resoldered the IDC connector about 5 times. It will then sometimes start, but if I move the cable around it stops working. I've tried different cables. I've also tested all the connections from the LowerROM to the edge connector test points (well, not really test points, I think they are the holes for connecting a centronics connector). I tested each connection while waving the cable around, and they all came through fine.
In short, I'm at a bit of a loss. It's clearly a connection problem, but I'm now guessing it must be in the CPC itself... though I don't quite know how... apart from anything, the CPC looks as though it could have been made yesterday, it's so clean and new.
Indeed, it is FW3.12. The standard firmware will not boot from the LowerROM either.
Any ideas?
Just tried the LowerROM on my 464, and it works beautifully :D
So I plugged the symbiface into it, and FW3.12 reports "RAM: 560K"! :D :D
I didn't even know extra RAM would work with the 464, because it lacks the banking mechanism - what's going on there?? And why does it not report 576K?
The only thing is, I don't get the symbos ROM boot logo. So I tried the symbiface back on my 6128 afterwards (without LowerROM), thinking the ROMs weren't being initialised for some reason on the 464, and I don't get it there any more either. Could it have become erased somehow? Could the LowerROM have caused it? I hope I haven't damaged my Symbiface at some time ???
So now all that remains to do is:
1) Figure out what on earth is wrong with my 6128 (suspect bad connection in the CPC somewhere).
2) Get the ROM manager/other ROMs on to floppy disc or tape, so that I can actually boot some stuff, and test that the symbiface is definitely working 100% (most worried about this as it costs a pretty penny and is hard to replace).
Can rom manager and stuff be run from a 464 with the tape deck? Not that I have any way to make tapes, but I have one of those tape->3.5mm jack adapters, so I could plug it into my PC and play tapes to the 464 (I just got a replacement tape drive for my 464). Is there a tool to convert .dsk to .tap?
I STILL have no way to make floppies (3.5"). Don't suppose anyone wants to volunteer to make me a couple and post them to me? I'll happily pay for the discs/postage/time.
Thanks for your help guys!
Are you sure you haven't just disabled the SF2 ROMs while you were experimenting?
As they are stored in a battery backed RAM, you may have also shorted the supply by mistake which would also erase the RAM-ROMs. The LowerROM Board wouldn't erase anything on the SF2.
Bryce.
They weren't disabled no, I double checked. A short is much more likely though - I think I accidentally shorted 5V to GND at some point for a split second (though the symbiface is on the 12V line of the same supply), and I'm not sure if it was before or after testing (I do remember that it was while the CPC was off though), but would that do it?
I didn't even know a short will erase the RAM... hopefully that is the cause. I could have shorted it accidentally at another time and not noticed (my PSU setup is a bit of a mess ATM).
Bryce, do you have any particular suggestions for checking the expansion port lines inside my 6128? I don't know where they all go, but I think some are direct to the z80 and some to the gate array? I guess I'll have to get the schematics and trace each line individually.
No, the only way to properly test them is to test each one individually with an oscilloscope or a Logic Analyser.
Bryce.
Hmm, that's a bummer. I have a 1MHz scope, but that's too slow, right? I guess the scope/logic analyser is needed because the fault is intermittent and hard to trace?
I will try using the continuity tester on my multimeter, to see if that can find anything. If I don't I guess I can re-solder all the joints and hope I catch the problem. Does that sound reasonable?
Thanks.
A 1Mhz scope is fine, you're not trying to read the pulse lengths, only their levels. Connect it to one of the data lines, set it to trigger on a positive edge with a trigger level of about 2V. When it triggers measure the voltage of the positive level. It should be 5V of course. If it doesn't trigger or the level is lower than about 4.75V then that's the pin giving you problems. If all is ok, move on to the next one. Do this for all Data and Address lines.
Bryce.
Great, now there's a plan! But it's back to waiting again, until I can retrieve my scope in a few weeks time :(
At least I can play with the 464 in the mean time :) I'm going to make some tape images and convert them to wavs
I only just thought this through enough to realise that I can't do much testing of the symbiface with only a tape drive anyway, because even if I load the ROM manager I'll have nowhere to load ROMs from without a disc drive! D'oh!