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Multiface 128 problemHello everyone i have a 48k plus speccy which i firstly thought was working perfectly. It passed all the test of the official Sinclair test tape (cpu…
... because of non-(good)-working M1 line?[/QUOTE]
Really? I ... -
Some things I bet you didn't know about Microdrives...Quote: This can be attached to any 16k, 48k, & 128k Spectrum Computer, it always for increased performance, and more detailed BASIC code. The Micro …
[QUOTE=DEATH]There were many many Spectrums released with bad NMI lines resulting in things like IF1, Multiface, +D disk interface etc not working.[/QUOTE]
The IF1 uses NMI? I thought problems were down to a dodgy M1 line.
MikeW -
Some things I bet you didn't know about Microdrives...Quote: This can be attached to any 16k, 48k, & 128k Spectrum Computer, it always for increased performance, and more detailed BASIC code. The Micro …
[QUOTE=MikeW]The IF1 uses NMI? I thought problems were down to a dodgy M1 line.
MikeW[/QUOTE]
Well, OK, same difference as makes no odds :D
I think the IF1 uses NMI though - maybe not, I have learned someting today! -
Some things I bet you didn't know about Microdrives...Quote: This can be attached to any 16k, 48k, & 128k Spectrum Computer, it always for increased performance, and more detailed BASIC code. The Micro …
... correct NEC Z80 had bad M1 line.[/QUOTE]
Probably wrong ... a problem with a faulty M1 line (resulting a Multiface128 not working ... recall) i tested had faulty M1 line.
Finally a NEC Z80 ... -
Nooooo my speccy died!??!!Hi! I am quite sad. :( Tonight I got a kempston interface so I rushed home to try it on my spectrum+ The edge connector of the interface was narrower…
... , RAM) inclucing the Z80's M1 line (they didn't have extensive ... -
Compatability with Interface 1 and SpeccyI was wondering if there are any known compatibility issues with different versions of the Speccy and the Interface 1. Reason I ask is I have a vers…
Check CPU.
Some brands have faulty M1 line, and therefore some interfaces work not. -
Compatability with Interface 1 and SpeccyI was wondering if there are any known compatibility issues with different versions of the Speccy and the Interface 1. Reason I ask is I have a vers…
What's the nature of the fault of the M1 line? Does it simply never go active, stay permanently active, or is the timing screwed up? -
Compatability with Interface 1 and SpeccyI was wondering if there are any known compatibility issues with different versions of the Speccy and the Interface 1. Reason I ask is I have a vers…
[QUOTE=Winston]What's the nature of the fault of the M1 line? Does it simply never go active, stay permanently active, or is the timing screwed up?[/QUOTE]
Ask someone with logic analyzer.
Or answer to first 2 questions with voltmeter :D -
MultifaceOne Vs Multiface128Is there any advantages to having a Multiface128 as opposed to a MultifaceOne for the 48k rubber speccy? Currently I have the M1 and sometimes get s…
... ?
It might be a M1 line (NMI) mulfunction of the Z80 ... -
Blowtorch method of Speccy repairsI just did my first Spectrum repair (and successful at that). It was the Issue 2 spectrum I wrote about a while ago, I just hadn't got around to doin…
... you can test Z80's M1 line (NMI).
I had a ... would just reset. If the M1 line doesn't work you will ... -
MultifaceOne Vs Multiface128Is there any advantages to having a Multiface128 as opposed to a MultifaceOne for the 48k rubber speccy? Currently I have the M1 and sometimes get s…
Yeah but Im sure its not the M1 line thing. I just put a new Z80 in it and that fixed the other M1 issues I was having with the interface one. I was thinking its probably 'wobble' when I am hitting it. -
MultifaceOne Vs Multiface128Is there any advantages to having a Multiface128 as opposed to a MultifaceOne for the 48k rubber speccy? Currently I have the M1 and sometimes get s…
... Im sure its not the M1 line thing. I just put a ... and that fixed the other M1 issues I was having with ... you can rule out the M1 line problem entirely).
When ... -
MultifaceOne Vs Multiface128Is there any advantages to having a Multiface128 as opposed to a MultifaceOne for the 48k rubber speccy? Currently I have the M1 and sometimes get s…
... you can rule out the M1 line problem entirely).
When ... -
Multiface 128 WoesI have a customer who has a couple of Mutliface 128s which are not working. He has managed to save some snapshots (and reload them) in the past, but…
If it's not the Spectrum's M1 line, it must be the paging logic. Luckily, all the chips can be bought off the shelf, except the RAM and the ROM. Would probably be an easy fix for somebody "in the know". -
Faulty M1 linesI'm sure this has been discussed before, but using the forum search for the word 'M1' pulled back no hits, which surprised the hell out of me. Anywa…
... So I drilled out the M1 line on my test board, ... timing issue (although the M1 line would have to be ... instruction).
The M1 line isn't actually needed for ... Z80 has a faulty M1 line). I still want to ... scope probe on the M1 line to try and figure ... -
Faulty M1 linesI'm sure this has been discussed before, but using the forum search for the word 'M1' pulled back no hits, which surprised the hell out of me. Anywa…
... So I drilled out the M1 line on my test board, ... timing issue (although the M1 line would have to be ...
[quote=Winston;181349]The M1 line isn't actually needed for ... Z80 has a faulty M1 line). I still want to ... scope probe on the M1 line to try and figure ... -
Testing RAM Chips After RemovalHi I am going to use Winstons Hot Air Gun method of removing the RAM chips from a 4S circuit board. I wish to check the RAM chips, I have a Logic Pr…
... PCB layout for 'use M1 / don't use M1' to allow for ... to test the CPU's M1 line.
I've designed ... on power up. The WR line on the flash chip is ... -
Spectrum Diagnostics Board - 25th Anniversary projectWell, I said I'd try and get something online about this by today, and I have indeed done so. This web page still needs finishing off (in particular,…
... - such as the CPU clock, M1 line, address and data bus lines ... -
Interface 1 electrolytic capacitorsInterface 1 has three 47μF electrolytic capacitors. Is it necesary to replace them with fresh ones? I always do this with old speccys but is it…
... the Z80 with the dodgy M1 line - only a problem if you ... -
Printer InterfacesI have a customer who wants to connect an Epson 850 printer to a humble rubber key Speccy. Now I happen to have 3 printer interfaces (all Kempston) …
... standard Z80 (it's the M1 line I think), there's every ... -
Printer InterfacesI have a customer who wants to connect an Epson 850 printer to a humble rubber key Speccy. Now I happen to have 3 printer interfaces (all Kempston) …
... standard Z80 (it's the M1 line I think), there's every ... don't rely on the M1 line but monitor IORQ and WR ... only every active simultaneously when M1 would be active so you ... can get around the M1 not working problem that way ... -
Input/Output on Edge ConnectorI would like to sense a pulse on the data bus via the edge connector, i.e. on or off. How do you decide what port it is on? I would also like to send…
Out of interest, is it actually necessary to decode the M1 line? Under what circumstances would IORQ go low when it wasn't a port access? -
Input/Output on Edge ConnectorI would like to sense a pulse on the data bus via the edge connector, i.e. on or off. How do you decide what port it is on? I would also like to send…
... special M1 cycle when the Z80 acknowledges the INT line, where ... IORQ goes low and M1 goes low ... 't pay attention to M1 then interrupt acknowledges can ... to use is IORQ+M1 since you need one ... you can test the M1 line by jumpering M1 (quite a few ... -
Input/Output on Edge ConnectorI would like to sense a pulse on the data bus via the edge connector, i.e. on or off. How do you decide what port it is on? I would also like to send…
... actually necessary to decode the M1 line? Under what circumstances would IORQ ... -
Interface rom - Need help to dump itHi, I have temporarily an interface that is similar to a multiface. It has an NMI button and displays a menu where states can be saved and pokes ent…
... the interface does decode the /M1 line from the Z80.
This line goes active (0 volt) whenever ... address' contents as data, so /M1 is inactive when accessing it ... -
Interface rom - Need help to dump itHi, I have temporarily an interface that is similar to a multiface. It has an NMI button and displays a menu where states can be saved and pokes ent…
Interface rom - Need help to dump itHi, I have temporarily an interface that is similar to a multiface. It has an NMI button and displays a menu where states can be saved and pokes ent…
... presumably doesn't monitor the M1 line). I extracted it by calling ...Rom dumping a Mirage MicrodriverI need to dump the rom of my Mirage Microdriver for Zub and don't know what to do...any help?
... whether the IORQ line is wired, or the M1 line is wired or ...
