My Turbo MMC Misadventures

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Balmoral James
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My Turbo MMC Misadventures

Post by Balmoral James » Mon Jun 18, 2018 9:09 am

Hi There,

I am a total newbie to the BBC Micro and recently have been enjoying my Acorn Electron but wanted to get my teeth into the behemoth that is the Beeb. So I bought a recapped/refurbished machine that has a copy of Snapper included on a Rom, I have been buying games from eBay and playing the Electron games that are BBC compatible and have been having a blast with it, what a fine machine it is.

Being an owner of the C64 and Spectrum (sorry about that)- I have naturally gone down the road of sd card solutions for those systems as tapes.....well you know! I thought I would treat myself to a Turbo MMC for the Beeb and there began the misadventure......

My ageing PC struggles with Adobe so I wasn't able to see any instructions but I had watched a lot of videos on YouTube and read a bit so I thought..."How hard can it be?" I'm sure it isn't but I reckon I've made a bit of a pigs ear of the process- as you read on I'm sure you will probably tear your hair out and to be honest I wouldn't blame you.

For a start I put the Rom in a spare socket first, I was really nervous of this bit so I thought I'd get it out of the way. In my wisdom although I hadn't connected the drive and cable to the Beeb I thought as I'd done that I'd power the machine up just to check whether the machine would recognise it. I turned on the Beeb but instead of the friendly beeps-all I got was a lower pitched beep and a black screen with a solitary flashing cursor and a horrible feeling in the pit of my stomach!

In a blind panic I turned off the Beeb because I now feared that I had done something very wrong with the installation, I left it for a minute and turned it on again- same result. Feeling even sicker I decided to remove the Rom and see if the computer behaved normally. Long story short- it did- so I was relieved- but despite what I thought was a gentle removal of the Rom chip I noticed that some pins at the edge were bent. I tried to straighten them but....you can see where this is going can't you.....the pins broke. I was sick to the core but the Beeb seemed ok so I was going through mixed emotions.

I explained all to the fine seller on eBay (I'm sure they probably post here as all the stuff they were selling was Acorn related) and explained that I'd been a chump and that I would leave good feedback for them because it wasn't their fault that I was such a dimwit where this is concerned. They were fantastic and assured me these things can occur and sent another Rom chip for which I am thoroughly gobsmacked at the kindness and generosity considering this was my balls up.

Fast forward to now- I have to confess that I am still plucking up the courage to try again because I'm paranoid about messing up- but at the same time I really want to experience this device. So please be gentle everyone for I have some questions because I need a bit of help and advice. Bear in mind I'm a newbie! (Although I accept ignorance is no excuse for stupidity and ineptitude!!)

1) How close was I to completing the original installation before I panicked or was I way off and doing it all wrong?
2) If I had left the chip in then connected the cable and card reader then powered on- would everything have worked out ok?
3) If I had somehow seated the Rom incorrectly (though I believe it was the right way up and I did push it down gently but firmly) can the it be removed safely and easily without causing any damage to either Rom chip or BBC and if so what is the best way to do that??

Many thanks to any of you who have waded through all that and are endeavouring to come up with an answer to one or any of my questions, for that bravery alone I would like to thank you in advance! I'm hoping somewhere along the line this fine community will be able to throw a lifeline to a struggling newbie!

But as I said earlier- Please be gentle :D

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BigEd
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Re: My Turbo MMC Misadventures

Post by BigEd » Mon Jun 18, 2018 9:21 am

Ouch! Glad to hear no permanent damage was done. The trick to removing ROMs is to be very gentle and progressive, lifting them as close to parallel as you can. Usually that means trying to lever up from both ends, one at a time, gradually getting it out in a dozen tiny movements.

As for what went wrong, I don't know. Certainly you do need to get the ROM the right way around, and in an appropriate socket! And all the pins in the right holes. And no pins bent under or bent out, which can happen. Again, using lots of care and close observation to line everything up.

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danielj
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Re: My Turbo MMC Misadventures

Post by danielj » Mon Jun 18, 2018 9:22 am

Hi James :) No such thing as stupidity, everything is a learning process.
Balmoral James wrote:
Mon Jun 18, 2018 9:09 am
1) How close was I to completing the original installation before I panicked or was I way off and doing it all wrong?
ROM in, connect cable, away you go. You shouldn't have got a beep/flashing cursor, the beeb will still work with just the ROM inserted.
2) If I had left the chip in then connected the cable and card reader then powered on- would everything have worked out ok?
Nope, sounds like the ROM wasn't in properly.
3) If I had somehow seated the Rom incorrectly (though I believe it was the right way up and I did push it down gently but firmly) can the it be removed safely and easily without causing any damage to either Rom chip or BBC and if so what is the best way to do that??
So, the notch should be towards the back of the machine, inserting I tend to make sure one side is lined up first, rest those pins in the socket, and then get the other side rested in, again making sure all the pins are in, before pushing gently down at the top and bottom at the same time.

As Ed said, to remove, you need a flat bladed screwdriver, or the blanking plate from an slot on a PC (the l-shape is useful for getting into tight spots), just get it under the top edge and lever it up a little, then do the same at the bottom edge, keep alternating until it's free from the socket. Don't use an IC extraction tool, you'll get bent pins and send the thing flying :D

d.

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Elminster
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Re: My Turbo MMC Misadventures

Post by Elminster » Mon Jun 18, 2018 9:54 am

I have a set of these for inserting and extracting.

https://www.jonard.com/Products/WK-7-IC ... action-Kit

Edit: but I don’t use the tweezer looking ones on acorns.
Last edited by Elminster on Mon Jun 18, 2018 8:14 pm, edited 2 times in total.

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danielj
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Re: My Turbo MMC Misadventures

Post by danielj » Mon Jun 18, 2018 10:01 am

Elminster wrote:
Mon Jun 18, 2018 9:54 am
I have a set of these for inserting and extracting.

https://www.jonard.com/Products/WK-7-IC ... action-Kit
I'd strongly advise against using this: https://www.jonard.com/Products/Product ... 22843999A4}

I've seen more ICs destroyed by these than removed successfully...

dominicbeesley
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Re: My Turbo MMC Misadventures

Post by dominicbeesley » Mon Jun 18, 2018 10:42 am

The good thing about the beeb is that it is pretty tough. I regularly manage to put chips in the wrong way round etc and so far I've not killed one. When I had Spectrums they seemed to die if you so much as looked at the expansion connector sideways!

I use one of these for most of my dip IC removal. It's the lug from the back of an old PC. The narrower tongue is good for levering, is made of a fairly soft metal so less likely to cause damage.
20180618_112321-s.jpg
20180618_112316-s.jpg
When inserting new chips what is often not clear is that the pins will be splayed out by too much, they usually need to be carefully bent in by pressing down on a desk.

i.e. this is how they look out of the box, legs splayed out by ~2mm
20180618_113305-s.jpg
Press down on the desk gently until they legs are all even and straight (use both hands, I needed the other to hold the camera)
20180618_113343-s.jpg
It should look like this:
20180618_113412-s.jpg
When placed on the socket the pins should naturally line up with the centres of the holes of the socket, if not you may need to adjust closer or further apart. If you need to spread the pins use a ruler or similar to gently prize all the pins together. Avoid the temptation to adjust pins individually they can weaken quite quickly!

D

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jms2
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Re: My Turbo MMC Misadventures

Post by jms2 » Mon Jun 18, 2018 11:08 am

Sorry to hear about your problems and well done for seeking advice!

I've only got one thing to add to the comments above, which is that you don't need to be stressed and nervous when inserting/removing ROMs. It's not really a high risk process, you don't need to wear an anti-static suit or be in a clean room. You just need to make sure:

1) The rom is the right way round
2) Don't bend the legs.
3) Don't drop any metal objects into the Beeb (obviously)

In this case, it sounds like you've fallen foul of (2) but if you pre-straighten the legs as described above everything will be fine.

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tricky
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Re: My Turbo MMC Misadventures

Post by tricky » Mon Jun 18, 2018 12:32 pm

If you are in the vicinity of an ABUG meetup, drop in and someone will do it for you (although from your name there isn't one soon).
If you are confident, it is quite easy, but you do need to do a few to get confident!
I have inserted and removed hundreds of ICs over the years, but still occasionally bend pins removing them and rarely inserting then (usually cheap ebay recycled chips).
As has been said, make sure that the legs are straight and fit into the top of the holes without pushing and then push them straight in.
If you have a choice of sockets, you might pick one that has easy access to the top and bottom, although you shouldn't need to remove it, it might give you a little more confidence.

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Elminster
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Re: My Turbo MMC Misadventures

Post by Elminster » Mon Jun 18, 2018 6:58 pm

danielj wrote:
Mon Jun 18, 2018 10:01 am
Elminster wrote:
Mon Jun 18, 2018 9:54 am
I have a set of these for inserting and extracting.

https://www.jonard.com/Products/WK-7-IC ... action-Kit
I'd strongly advise against using this: https://www.jonard.com/Products/Product ... 22843999A4}

I've seen more ICs destroyed by these than removed successfully...
Can’t say I have had an issue, I have damage things with screw drivers though.

Mileage varies I guess

Edit: I find them especially useful for those places on the mb where using a screw driver is impractical.
Last edited by Elminster on Mon Jun 18, 2018 7:02 pm, edited 1 time in total.

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danielj
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Re: My Turbo MMC Misadventures

Post by danielj » Mon Jun 18, 2018 7:05 pm

Elminster wrote:
Mon Jun 18, 2018 6:58 pm
Can’t say I have had an issue, I have damage things with screw drivers though.

Mileage varies I guess
Gently and carefully with the screwdriver and you'll be unlikely to have a problem. JGH summed up why these things are potential chip killers quite nicely:

viewtopic.php?f=3&t=12322&p=157672#p157672

You might not notice until you have a tight one, then bang - off it whizzes and destroys its pins. It's one of the few tools where I can't in good conscience advocate its use.

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Elminster
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Re: My Turbo MMC Misadventures

Post by Elminster » Mon Jun 18, 2018 7:09 pm

Oh right I don’t tend to use that one to be fair, I use the plunger one, which you hold against the board and the ones that put them in.

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danielj
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Re: My Turbo MMC Misadventures

Post by danielj » Mon Jun 18, 2018 7:25 pm

Elminster wrote:
Mon Jun 18, 2018 7:09 pm
Oh right I don’t tend to use that one to be fair, I use the plunger one, which you hold against the board and the ones that put them in.
That'd be better as it levers against something and won't suddenly "give" :)

d.

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Elminster
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Re: My Turbo MMC Misadventures

Post by Elminster » Mon Jun 18, 2018 8:10 pm

I edited my original post for you, I have used the tweezer things a couple of times on non acorns where chips are packed in close, but I take your point.

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danielj
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Re: My Turbo MMC Misadventures

Post by danielj » Mon Jun 18, 2018 8:18 pm

Och, no need! It's not really anyone's fault other than the people selling the darn things for that purpose - I used one a fair few years back in a tight spot and destroyed an IC - fortunately just a 74LS, but it certainly stuck with me!

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Re: My Turbo MMC Misadventures

Post by duikkie » Wed Jun 20, 2018 5:33 am

some dutch tricks , i think the uk people can translate it in good englisch

use double IC 28 pins socket. buy or get a good ic 28 pins socket , with good legs
not the chinees 0.05 pence things :) many someone in uk can put a picture which i mean ?

so you have a good empty 28 pins socket, put your rom in the socket outside the beeb
on a table or use a sort of pillow under the legs

be proud if you put the rom in the 28 pin socket, look around the 28 pin socket, is it not a wonder
all legs in the socket :)

the put the ic 28 socket with good legs and the rom together in a empty ic socket in the beeb

the pin 1 rom is the one with the dot left up , the ic 28 pin socket pin 1 /28 is with the smile up ???

understand anyone what i am talking about :)

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Re: My Turbo MMC Misadventures

Post by cmorley » Wed Jun 20, 2018 5:52 am

duikkie wrote:
Wed Jun 20, 2018 5:33 am
good ic 28 pins socket , with good legs
Duikkie is talking about "turned pin sockets".

This has the advantages duikkie mentions but there is a risk... the turned socket pins are fatter than a chip leg and may damage/bend the spring contacts in the sockets on the BBC. If you remove the socket later and try to insert a chip the original BBC socket may not grip all the legs properly - causing a bad connection.

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tricky
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Re: My Turbo MMC Misadventures

Post by tricky » Wed Jun 20, 2018 6:36 am

Image
The dual leaf contact type on the left are the most common, although you may not see the contacts so easily and they didn't usually have raised edges. The ones in your beeb are probably not very shiny either.
The turned pin contact type on the right, are easier to insert an EPROM into, but if you are a little clumsy,you might snap a turned leg off.
What duikkie means by pillow, is to support the middle of the socket while you insert the EPROM into it. If I am worried, I put the socket into the zif socket on my EPROM programmer to hold it. You could also use a small stack of through hole vero/project boards.

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Re: My Turbo MMC Misadventures

Post by dominicbeesley » Wed Jun 20, 2018 9:51 am

I'd strongly advise against putting turned pin sockets into BBC motherboard sockets. The ones in the beeb are quite soft metal which after thirty odd years is not as springy as it once was. I've had to replace most of the sockets in my main machine, often due to poking in things that I shouldn't! Once you've done this once you can't really go back reliably

D

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tricky
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Re: My Turbo MMC Misadventures

Post by tricky » Wed Jun 20, 2018 10:59 am

I have never added a turned pin socket to anything and the one thing in my Beeb with one has a sacrificial non turned one betweestred the beeb's socket.

I just wanted to do the translation of duickie's post.

I know plenty of experience hardware people on here use turned pin sockets, I personally don't but only because I don't want to stretch my Beeb's sockets as I tend to swap stuff about, not because I have anything against them.

dominicbeesley
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Re: My Turbo MMC Misadventures

Post by dominicbeesley » Wed Jun 20, 2018 3:21 pm

Not having a go at anyone, just sharing my experiences

Replacing the beebs sockets with turned pins is not a bad idea though...

However, the OP's problem is hopefully sorted!

D

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Elminster
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Re: My Turbo MMC Misadventures

Post by Elminster » Thu Jun 21, 2018 8:39 am

Semi on topic. I have been using these plastic thingy me bobs to remove ROM chips recently, just using a screw driver to get them going if a bit tight. I started using them after breaking an IC socket a few days ago with a screw driver (should have used the chip tweezers, broken EPROM more disarable than broken socket in this case! I blame Daniel.). They came in a tool kit designed for taking iMac's apart that I got ages ago when I changed my previous imac to an SSD. Here is a picture (of the tools, not an imac).
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IMG_3896.jpg

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sweh
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Re: My Turbo MMC Misadventures

Post by sweh » Tue Jun 26, 2018 12:38 am

Confession... back in the day I used to use the "bottle opener" blade of my pen knife to remove ROMs. The rounded edge of the back of the blade made a nice lever against the motherboard. It looked something like this:
bottle-opener.jpeg
bottle-opener.jpeg (6.14 KiB) Viewed 276 times
I didn't bend too many pins, and never broke any :-)
Rgds
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duikkie
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Re: My Turbo MMC Misadventures

Post by duikkie » Tue Jun 26, 2018 5:34 am

the problem with lifting a rom is the space around it
most of the time a cap or resistor blocks it :(

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danielj
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Re: My Turbo MMC Misadventures

Post by danielj » Tue Jun 26, 2018 6:45 am

That's where the old blanking plate from a PC card slot works wonders. I use the hard drive bracket from a riscpc at the moment :D

d.

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Elminster
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Re: My Turbo MMC Misadventures

Post by Elminster » Tue Jun 26, 2018 8:35 am

danielj wrote:
Tue Jun 26, 2018 6:45 am
That's where the old blanking plate from a PC card slot works wonders. I use the hard drive bracket from a riscpc at the moment :D

d.
Or use IC Extractor Tweezer :evil: Who said that !!??..... (Although you could rock them back and form which might not chop IC in half)

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Re: My Turbo MMC Misadventures

Post by cmorley » Tue Jun 26, 2018 8:53 am

I just use a 16oz claw hammer. The curved end is perfect for lifting stubborn chips and you can tap them back in with the hammer end. :roll:

Sorry only joking. I don't use a 16oz... 20oz is better. :lol:

Really though... I find a small screwdriver best and this metal spudger is great for sliding under 40 or 48 pin DIP chips. Got it from eBay I think.
Photo0624.jpg

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Elminster
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Re: My Turbo MMC Misadventures

Post by Elminster » Tue Jun 26, 2018 9:40 am

I think the issue is when tight space. Dont suppose they do an angle spudger? The angled flatblade screwdrivers usual angled the wrong way.

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danielj
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Re: My Turbo MMC Misadventures

Post by danielj » Tue Jun 26, 2018 9:42 am

Elminster wrote:
Tue Jun 26, 2018 8:35 am
Or use IC Extractor Tweezer :evil: Who said that !!??..... (Although you could rock them back and form which might not chop IC in half)
:D

The trick is one end at a time, not both together.

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Re: My Turbo MMC Misadventures

Post by cmorley » Tue Jun 26, 2018 9:50 am

Elminster wrote:
Tue Jun 26, 2018 9:40 am
I think the issue is when tight space. Dont suppose they do an angle spudger? The angled flatblade screwdrivers usual angled the wrong way.
The spudger is angled. It doesn't show well in the top down photo... you can see better on the pointy end. The blunt end is similar.

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Elminster
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Re: My Turbo MMC Misadventures

Post by Elminster » Tue Jun 26, 2018 10:59 am

cmorley wrote:
Tue Jun 26, 2018 9:50 am
Elminster wrote:
Tue Jun 26, 2018 9:40 am
I think the issue is when tight space. Dont suppose they do an angle spudger? The angled flatblade screwdrivers usual angled the wrong way.
The spudger is angled. It doesn't show well in the top down photo... you can see better on the pointy end. The blunt end is similar.
Right angled? If so that sounds a very useful tool. Better than using the back plane covers off old PCs!

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