Fault with the floppy connector?

[CRG]

I was kindly gifted a couple of things for the CPC464 including the DDI-1 with floppy drive, a memory expansion and the serial adapter.  I was trying to get these working last night with little luck and I'm starting to think there is a fault with the CPC itself rather than the expansions which were known good before they came my way.  

I've cleaned the edge connector but I've been told it might need more work as they are known bad, not sure though.  

Beyond that I'm trying to understand how it works, in particular the DDI as I feel if I can get that working the rest will fall in line.  From what I understand the DDI has a ROM onboard which when connected replaces the ROM on the CPC itself.  The schematic shows a rom disable line that runs between the onboard ROM and the expansion slot.  I think this will go high when the expansion is connected disabling the onboard ROM and allowing the DDIs ROM to take over.  Is this correct?  

I can find the schematics easily enough but I cannot find anywhere that shows the meaning of each line and what it does.  The voltages, data bus and address bus are easy enough and all look good but its the rest.  

I should note that the CPC itself works fine, it'll load games from tape etc.  When the DDI is connected none of the commands associated with that work, just throws a syntax error. 

[eto]

Did you try the DDI alone or connected to the working drive?

If not, this explains it. The DDI receives its power from the drive. https://www.cpcwiki.eu/index.php?title=Amstrad_External_Disk_Drive&redirect=no

The expansion port is documented here:
https://www.cpcwiki.eu/index.php/Connector:Expansion_port

The ROM on the DDI does not replace the internal ROM but enhance it. It is active in parallel to the internal ROM and all further external ROMs. The external hardware identifies when the external ROM is accessed and then puts a signal on the ROMDIS line, so the internal hardware is not accessing the internal ROM.
https://www.cpcwiki.eu/index.php/ROM
https://www.cpcwiki.eu/index.php/Upper_ROM_Bank_Number

[CRG]

While I have not checked I have been told the DDI was modified to take power from the CPC rather than rely on the floppy drive. Equally the floppy drive is modified to stop it powering the DDI.  Perhaps I should try to reverse this mod.  That said though I tried it both with the drive connected and disconnected, the result being the same.  

[eto]

Then probably it makes sense to first check if the DDI electronics receive proper 5V. 

Btw: I think it should be "unknown command" rather than a "Syntax error", if you are executing one of the new pipe commands that AMSDOS provides. If it is Syntax error, you might have skipped the pipe | before e.g. |disk.

[CRG]

I honestly can't remember the exact term on screen but it was an error.  I was placing the | before the commands. 

I'll check for power to be sure, its certainly getting to the edge connector but need to open up the DDI to check within it. 

Having never used a DDI before (I'm new to the CPC in general) I assumed the DDI and disk drive is just plug and play.  There are any commands I need to run to start it? 

Is there a handy list anywhere with the commands that relate to the DDI?  Simple stuff like list directory?

[eto]

Since you are completely new to the CPC it might make sense to read the manual of the DDI/FD-1 to get a better understanding how it is set-up and how it works: https://www.cpcwiki.eu/manuals/ddi-1.zip

The DDI/floppy is plug and play if it's set-up correctly AND nothing is broken. You attach it to the CPC, switch on the floppy and then the CPC => it should work out of the box.

As it's not working, something must be wrong and we now have to identify if it's just a set-up problem or if something is broken, and then what is broken. You already mentioned that the DDI was altered and that makes things slightly more complicated, that's why it's relevant to check different aspects, to get an idea what could be wrong. That's why I asked for the specific error message as depending on the error, there are different conclusions. Also it's different if it gets 5V vs. it doesn't (or far less than 5V).

Here are the additional commands that the ROM in the DDI provides:
https://www.cpcwiki.eu/index.php/AMSDOS

The Basic commands CAT, RUN, LOAD, CHAIN and MERGE will continue to work and use either disc or tape, depending on what you have selected with the respective AMSDOS command. 

[pacomix]

While I have not checked I have been told the DDI was modified to take power from the CPC rather than rely on the floppy drive. Equally the floppy drive is modified to stop it powering the DDI.  Perhaps I should try to reverse this mod.  That said though I tried it both with the drive connected and disconnected, the result being the same. 

Probably the previous owner simply disconnected the power line that goes to the ribbon cable. That's the very first to do when connecting the external FD1 drive to a PC for dumping disks. If so it is really easy to fix by simply opening the FD1 case and reconnecting the inner cable.

https://www.classic-computers.org.nz/blog/images/2015-10-06-amstrad-fdd1-no-5v-on-cable-800x.jpg

[Bryce]

Hi CRG,
     you've actually given us zero information so far, other than "I typed something and got some error". This tells us nothing. The DDI-1 has a ROM inside so let's use that to test whether the DDI-1 is getting power. Type |A and hit enter and tell us the error you get. If it's "unknown command" then the DDI-1 isn't getting power, so we can work from there.

Bryce.

[CRG]

Hi CRG,
    you've actually given us zero information so far, other than "I typed something and got some error". This tells us nothing. The DDI-1 has a ROM inside so let's use that to test whether the DDI-1 is getting power. Type |A and hit enter and tell us the error you get. If it's "unknown command" then the DDI-1 isn't getting power, so we can work from there.

Bryce.

I got it working, dirty edge connector so just a bad connection.  I had cleaned it with use of IPA and a cotton bud but after giving it another go with an eraser it works.  Sorry for what turned into a bit of a pointless post in the end but maybe it'll be a lesson to anyone in the future that you really need to properly clean that edge connector before assuming there is a fault! 

[Skunkfish]

Those edge connectors are a pain...

It's good that you got it working!