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I've replaced the CMOS chip but, unfortunately, it's made no difference :( I've also dug out my non-working A5000 Alpha so if the kids don't object too much, I'll try to get the scope out tomorrow and have a big repair session. Shame to hear the CMOS chip didn't solve it. Did you get any further wi...

Exactly!

I started looking as my Acorn data recorder is not behaving at the moment, so I don't want to be left unable to use my cassette collection... but seems like there are at least a coupe of modern recorders available off the shelf with the right connections

Humm... https://www.ebay.co.uk/itm/Cassette-DATA-player-suitable-for-BBC-Master-Electron-with-PSU-and-data-cable/172002990346 From the description: "They don't make cassette recorders any more but we found this player that will load data tapes into a BBC Microcomputer..." So why's this cas...

Just read through this from the start. Great work getting this far Ken. I hadn't realised the Integra-B connection from the title or I'd have certainly read through earlier. I've got a fully working Integra-B, so if you can't read one or both of your PALs, let me know and I'll take apart my beeb and...

Hello I converted the lemmings demo ADF from lemming demo ADF to an HFE with the default settings. First, and I'm sure you've worked out if you've played the game, but this isn't 'Lemmings', it's a nice freeware clone of Lemmings, if a little less polished than the original, called Lemings (one 'm'...

Very interesting, thanks Mark. In that case, maybe channels 2 and 3 are the 'strange' ones, as they both sit perfectly at &FFF0 with no change. Either way, I'll take a good look at the pcb later - it was in terrible condition when I recieved it early last year, and has already had a good scrub, ...

Quick update. I'm still getting some strange behaviour from the ADC on my issue 3 beeb... The original (suspect) ADC chip still appears to crash the computer occasionally even without the joysticks plugged in! But if I swap it for the known-good ADC from my issue 7 beeb, then the computer seems stab...

Thanks all. I've had time to investigate this further. First, using Martin's example code and tricky's information, I've determined the following about my dual joysticks and two ADC chips: 1) one of my joysticks has an intermittent fault :( 2) both my ADC chips are fine when the joysticks are workin...

Brilliant, thanks both, will try this tonight!

Are there any other standard tests with documented expected results eg. using resistors of known values, and reading the results? (only because I'm slightly suspicious of the joysticks themselves!)

My issue 3 beeb has been exhibiting strange behaviour from it's ADC recently. I first noticed this when I plugged a set of Acorn dual analogue joysticks in to test the analogue port. Playing 'Dogfight' I found that neither joystick responded with the direction controls, but the fire buttons both wor...

Interesting read. I've not managed to get a 250mb Zip parallel drive working with the original Iomega !Zip driver myself (on my A5000 and A4000), but I regularly use my 100mb Zip drive with this driver (although not a big problem for me as I only have a single 250mb disc in my collection!). Question...

That sticking 1 key is relatively easy to fix if a little scary to do. John's fix is the correct way... And it is most likely a small amount of contamination/dust between the membranes that is causing the dodgy key problem. But if it's only one key affected, I've often found with these keyboards, t...

Ah, brilliant, thanks for the link. Simple external decoding to add one extra drive by treating drive 1 as being "NOT drive 0", now it makes sense! Neat solution in the article, and even neater laid out on your pcb.

Interesting, I've not seen this cable modification you mention, but I'm not sure how it can work without picking up the extra motor-on and drive select signals, at least on the A3010? These aren't tracked to the pcb floppy socket on the A3010, so it's one drive maximum unless you pick up the signals...

I've been looking at the A5000 TRM lately, but I can't figure out how you worked out the drive select address from these documents - I can see from the I/O system memory map in Fig 1-5 on p1-7 that the 82C710 is mapped to the region from &3010000 to &3011000, but I can't fathom how you work...

Glad it works :) One thing to be aware of if using this to swap two real drives (not Gotek) is that in the eyes of ADFS, this patch is equivalent of swapping the physical drives at the connector. So the drive step settings are also swapped. This initially confused my 5.25" external drive, and m...

Wow! Well done! Looking forward to some free time to play this at the weekend.

My thought was, wouldn't it be better to intercept the final stage of the process when ADFS sends the drive select/motor-on message to the FDC? Working on the assumption that ADFS used only one piece of code to do select a drive (why would you use more?), and providing this routine could be tracked ...

Thought about this for a couple of hours tonight and I now have a 100% robust software solution, tried and tested on my dual drive A5000. Daniel - which drive connectors did you plug your floppy and Gotek into on the A5000 PCB? I'd guess at PL10 for the floppy and PL11 for the Gotek? Or did you use...

Thought about this for a couple of hours tonight and I now have a 100% robust software solution, tried and tested on my dual drive A5000. Daniel - which drive connectors did you plug your floppy and Gotek into on the A5000 PCB? I'd guess at PL10 for the floppy and PL11 for the Gotek? Or did you use ...

RobC wrote:Definitely try reflowing as it fixed on fibble's too. I just applied some no-clean flux around it and then touched each pin with the iron.

Thanks Rob, I'll definitely give that a try

Found some rom images, will investigate. Oh yes, the wizzo ROMs are further up this thread. There's a choice of either a 32kb ROM or a later 64kb ROM. I've been running the 32kb ROM in my A5000 for over a year with no issues, you just need to mount it in the lower pins of the extension ROM socket a...

One other thing I thought about was the hanging issue that affects A4s. This eventually resulted in my A4 being dead until I reflowed the IOC. However, I've tried reflowing all the main chips and that hasn't brought the A5000 back to life :( Out of interest, did your A4 give any POST error messages...

jgharston wrote:Coming back to this, is there any chance you can save the Mertec Compact Companion control ROM so I can archive it.

I'm sure I've got one of those in the loft. Won't be going up there for a while, but will put it on my list to bring down if no one else has one to hand.

Bat wrote:The noise from the speaker has certainly decreased since replacing C19 and C20 so it's improved PSU noise filtering.

Great, that's definitely worth knowing about

Have you got the A3000 TRM?

I'm sure there's a diagram in there showing the internal expansion dimensions, along with the circuit and layout of the internal User port/MIDI podule?

If you don't have this, I can dig this out and post a picture when I'm home on Friday.

4 Partitions on one drive up and running... IDEDisc6,7,8 - still running solid state disk too. Interesting, the IDE disc formatter allowed me to create 6 partitions, likely could have created more. Unsurprisingly the filing system recognises the first four it finds - I presume. I'm sure internally ...

Hi, I've only got 2 BBCs but have noticed a fault on both PSUs which is not covered in the normal replacement parts kit you get on the well known auction site. The kit deals with caps on the high voltage side of the PSU, the ones I'm noticing are the output smoothing caps C19 and C20. They fail in ...

Sorry to hear about your A5000. I've had exactly the same too, and posted about it a while back: http://stardot.org.uk/forums/viewtopic.php?f=16&t=9378 Exacty like SteveB has said above, my A5000 would intermittently boot up if you pressed reset repeatedly after switching on, but it got progress...

Thanks for this post! I now have an IDE/SD card reader working on an A5000 under IDEFS booted from floppy formatted ADFS. The SD card reader would not work under ADFS. Great to hear that! If it works with the floppy boot disc, you can avoid this on the A5000 by finding someone to burn an extension ...