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Ahhh, something small and sweet arrived today:
And they grow so fast:
Here's hoping it becomes a useful member of society. I'm waiting on the stereo sound socket to arrive. Once soldered in I hope it turns out to be functional... If so I have a few boards, but be warned; because the board is pretty well packed it's a somewhat tricky job to solder.
Fingers Crossed
stereo AY audio?
also why does it need two via's? im curious
what is it? (add cat from red dwarf here)
It's a Sound card for the Apple II's... Need 2 6522 VIA's to interface the both AY's to the Apple Bus slot
:)
Charles.... Looking good my friend, hope it works ;)
looks i have an excuse to get a apple II,lol
I recomend picking up an NTSC iie Roy, you will get proper NTSC Woz Colour, read up on it, pretty impressive design.
If you need a 240v supply for it i can help you out.
They are fascinating machines for hackers, lots of projects to fill the slots, and the software is pretty cool too.
See Charlie's Pi interface.. works really well.
:)
is there a thread somewhere so i can have a peek?
Nice one, Charlie!
Does the IIGS benefit from this?
Man, I'm really beginning to itch for a IIe Platinum.
Hi chaps,
Thanks for the replies. I'll be frank and admit I'm very new to Apple hardware - I tend to have an unfortunate habit of jumping right in with a system that's new to me:
"Well that's all well and good but I want x,y,z to make it properly nice to play with... Oh, x,y,z are that hard to find and THAT expensive? B*gger that I'll make my own." Having a relatively simple expansion system and being typically expensive Apple kit has spurred me on a bit.
Anyway I see no reason why a Mockingboard shouldn't work in a IIgs but I have heard it's very hit and miss... I've still hardly touched mine as I have been busy getting my IIe up to scratch.
MockingChick:
Well, the correct stereo sockets have arrived so I've now tested it and... No dice, sadly. "My" design, such as it is, has no amplification on board to keep component cost and size down but with external amplification all I'm getting is a bit of system hum.
Both 6522s are a little warm with power applied but if I remember correctly from my Beebs that's not unusual. I am, however, not going to make the mistake I made with my A2Pi board by spending hours fruitlessly debugging to the point where I made a fresh design only to discover it was just a faulty IC that was to blame. I'll just do a sanity check on the power lines to be sure I'm not shorting anything and source some replacement ICs first...
...having said that I'm well aware I'm in over my head with regard to this kind of stuff so if anyone feels like casting an eye over my "simple" board design I'd be grateful. AmiOracle thread).
An update:
New parts on the way... but I've decided the MockingChick's current design is rubbish! Also there's a few mistakes on the PCB, and applying patch wires is so messy.
Rather than continue mashing bits of other designs together for my 'quick fix' I've actually bothered to engage some brain cells and do a proper design of my own to squash mistakes, make the board more functional, and fix some long running Mockingboard issues.
Goals:
Smallest possible PCB (cost)
Better physical compatibility with cards in a lower slot
A little easier to solder
More coherent and hopefully stable schematic
Better labelling
Audio jack will allow automatic switching between internal and external output
Also:
Headers for optional plug in Amplifier module
Long running Mockingboard reversed stereo fixed
A system beep pass-through that doesn't render the board mono
Long standing Mockingboard reset bug fixed
Sadly:
No speech; the ICs are stupidly expensive and it's just not worth the PCB real estate when I can't see the sockets getting populated.
Why not use one 6522? Very good question, the 6522 has more than enough IO to drive two sound chips but as I have no idea how the software works I didn't want to introduce compatibility issues, so stuck with the traditional design for now.
So...
One last check over, final fiddle with some of the labels, and yet another order sent to Seeed... fingers and toes crossed!
An update:
I think it's safe to say I'm fairly clueless at this PCB designing lark... Can't get my prototype to work, killed my Apple IIe, house slowly filling with coasters that look suspiciously like PCBs...
Ho-hum, marching on regardless. :)
I'm up to a Mk4 version of the Mockingchick. Finally got all the ICs to fit on one side of the board, keep the size down to a minimum and managed to route it. Phew! Piccies below:
Features:
Smallest and so cheapest PCB I can fit a full stereo Mockingboard clone on to.
Finally got all the ICs to fit on one side of the board so no chance of issues with boards in a lower slot.
Minimal component count to keep cost down. (diodes and R3 can be omitted with little loss)
Line out via 3.5mm audio jack that will line up with a knockout if using the default slot (4).
System sound pass-through header. (R3 either a resistor of your choice or use a variable pot)
Optional 4 watt amplified stereo out header for mounting internal speakers
Internal amplified audio auto shut-off if 3.5mm out in use.
Left and Right channels not reversed with this version.
No reset bug here!
For any who are interested I incorporated a header for one of these 4w stereo audio amps based on the PAM8403:
Cheap as chips at 99p a pop if you shop around. Surprisingly solid results, and both smaller and much cheaper than anything I could have incorporated in to this board. Don't need? Don't bother to fit. Have better plans for the headers? Be my guest.
No, this board isn't manufactured, yet. As my previous PCBs have proven very reluctant to get working I'd very much appreciate some advice on my schematic / layout before I inadvertently order another run of coasters.
Links to:
.zip file containing schematic and PCB files for MK4 board (and experimental version using Yamaha YMZ284s instead of AY-3-8913s)
Schematics for two common versions of the Mockingboard to compare with mine.
...for anyone who's feeling kind enough to do a sanity check for me, or anyone curious.
(I'm aware of the lack of decoupling caps for the ICs. They are present in a small revision not shown here)
Many thanks in advance. :D
I do hope the finishing line is in sight:
Yep, those ICs are pretty tightly packed. The board is really designed for the ICs to be soldered directly but this initial version uses pinstrip headers so I can debug any remaining issues (I hope not!) and have a test-bed for components on shipped versions. (assuming there's any interest) The whole thing sits very nicely in slot 4, and no conflicts with slots 3 and 5.
No errors from my IIe this time, but I've yet to test it software as I have a dead FDD/Card ATM. *Sigh* Will post the news once I have a working system.
Awesome awesome awesome!
:blushQuote:
Originally Posted by iainjh
Thanks for the very kind comment! I'm a bit frustrated because this little project has been rather more tricky that I hoped/expected, and now I sincerely hope I've cracked it I'd like to go test the darn thing. But no current way to load software without a working floppy. I guess I could ADTPro over audio but that would be painful!
Didn't we trade a super serial? Ps I tried over audio. It works -and is not that slow!
:)
ps push push eh.
Small Update:
As my Apple II is with the most excellent TC in the hope he can bring it back to life my MockingChick project is stalled with the hopefully final prototype ready for testing. So I thought I would have a crack at a manual / assembly guide.
Feel free to have a look, feedback welcome.
The postman has been good to me today:
Attachment 126257Replacement Apple IIe Motherboard
Having stupidly killed my Platinum's motherboard, and Humpty has refused to be put back together again, my 'pute has been officially brain dead for a bit. Most frustrating, especially as my first Mockingchick has been assembled and ready for testing for some time. I do hope the pesky thing works after all this.
Yes, it's a IIe, not a Platinum, board but as it's got a 65C02 in it I'm hopeful it will be functionally the same. Interestingly said 65C02 is a 10mhz WDC part. I understood Apple II's don't like these CPU's without moding; none noted but the seller claimed it's fully working and "refurbished" so let's see. Every IC is in a socket, which is nice, but equally every socket has been hand soldered so I guess this board has had a lot of work. Thankfully the PCB looks in good shape and I have a ready supply of spares. :oops:
Happy days, I do hope I'll have some good news to report shortly.
If when you boot it you get an ' Apple iie ' Logo not Apple IIe then you have an enhanced ROM set which is 100% compatible with the Platinum, if not we need to blow you some new ROM's
:)
Thanks Bas. :)
I finally let my ADAM alone long enough to put the 'new' board in my Apple II. The good news is it works and at first glance seems to be a IIe enhanced board, excellent!
Right, Mockingchick:
No sound from either the line out or amp out. Blast, I could have sworn I'd ironed out all the bugs.
Testing with a Mockingboard hacked version of Zaxxon, just in case I'll write an official Mockingboard demo disc...
I couldn't make my mind up between a 7404 or 7405 for the logic, makes no odds which I use except no activity LED with a 7405.
As I have loads of 6522s and AY chips I tried swapping a few, still no sound.
Too stingy with the decoupling caps? Still no joy after adding some direct to the ICs.
Did I get the diodes the wrong way round? Removing them didn't help.
One of the schematics I've seen has a load of passives round the 7404/5 for what looks to be an attempt at getting a better clock signal. I might try bodging that in but otherwise I'm sorry to say I'm out of ideas. Really frustrating, I'd swear building one of these boards should be pretty straightforward but I'm obviously missing something.
good news re the enhanced board working!
and... good luck with the mockingchick. any way to further test the board routing and addressing? btw why does it have to be slot 4?
Ahh... IIe fully reassembled and working well. Sadly the same can't be said for my Mockingboard clone. (grumble)
I do hope it's just the only Mockingboard aware software I have is a hacked version of Zaxxon which isn't working for some eason, and other software will be fine. Sadly I'm not hopeful.
Hi Iain,
To the best of my knowledge all Mockingboards will work fine in any slot but slot 4 is recommended because some software either doesn't auto-detect or ask and just assumes. Not in slot 4? No show.
Well bu**er me sideways with a pitch-fork!
For the life of me I couldn't work out why my Mockingchick board wasn't working. As one last test before I went through another redesign, having re-re-re-checked my version against every other schematic I could find, I wrote Sweet Micro's test disc over the supposedly Mockingboard enabled copy of Zaxxon I had been using and...
...It works!!! Ooo, my ears. The last because I had it plugged in to the portable amp I use with the band with the volume right up in case there was any sign of life.
So there you go. I'm not (quite) as stupid as I thought. (Bl**dy Zaxxon!)
Things to check:
-why does the computer lock up after the first demo screen? (I think because my board has no speech support)
-Is it truly stereo, and are the channels the right way round?
-does the amplified out work, and as expected shut off with a jack in the line out?
-does the motherboard audio mixing work, without pushing it in to mono? (Already spotted a mistake here but I think I only need to change a couple of components to fix)
-have I got the motherboard / Mockingchick mixing levels about right? (I guessed this but now I can hopefully test it)
As a nice bonus it's working with a 7404 rather than the 7505 logic I feared it might need. Not a Biggie but the former is much cheaper and easier to get hold of than the latter. I'll probably try some WDC 6522's at some point to see if they work too - the new WDC IC's don't work quite the same as the good old R6522P's, something to watch out for when making devices using this chip.
Pretty darn pleased to say the least! :D
Grr, bl**dy Zaxxon, grumble
well done!
asimov FTP has some test disks under hardwaresoundmockingboard, do you have all those?
Thank you, and thanks for the link I'll go have a nose about in a bit. The very good news is Prototype #4 seems to be fully functional!Quote:
Originally Posted by iainjh
I'm most pleased to report everything works as expected. The only thing that needed adjustment was the mixing resistor to get motherboard sound coming through the sound card at a similar level to the card's own output. The photos above show the first working prototype which is pretty much as the intended production boards will be. The primary difference will be boards I intend to make won't have socketed ICs, but I will MUCH prefer to send either bare boards or kits rather than fully assembled. (There are a lot of potential configuration options) In case anyone's wondering the black thing in the photo is a pair of speakers I salvaged from an old laptop to test the amplified header.
I shall go update my draft manual in case anyone is interested shortly, but for now I hope nobody will mind if I post the final features list:
Mockingchick, a 100% Mockingboard compatible sound card for the Apple II line of computersStereo sound card with six voices thanks to two AY-3-8913s
Works in any slot, although much supported software expects slot four
Motherboard audio may be mixed through the card without effecting stereo output
Line out for external amplified speakers
Amplified (three Watt) stereo header*
Automatic switching between outputs
Stereo audio the right way round
Will gracefully stop on system reset / crash
Minimal size and component count
Should not physically interfere with other cards
Plenty of scope for modification
Function LED
*The header is provided primarily to allow for internal speakers.
The card does not support voice synthesis. I did consider it but the necessary IC's are very hard to find and stupidly expensive.
Thumbsup! Reading the guide now.
Hey, I learned to do something new today. My very firstest video upload to YouTube to demonstrate my Apple II has a new trick up it's sleeve.
How many old computers can you spot, and can you name them?
I had a sneaking suspicion the laptop speakers I was using to test the amplified audio header were being driven a bit hard as they were actually getting too hot to touch so I went on a hunt for something more suitable. Happily I found an old iPod speaker dock that doesn't work with Apple's latest connector and so without a hint of irony butchered it to see if useful goodies lurked within:
Two 3w, 8ohm speakers, a plop load of wire, and some potentially reusable interconnect blocks. Hurrah! Close inspection of the photos will show my repurposing of these various bits 'n bobs to function as my new internal speakers, in action in the video above. The plan is to mount the whole thing, face up, under the Apple's keyboard using the screw posts from the remains of the shell as stand-offs. I'll probably go bananas with the old hot glue to fix it in place but if things line up nicely I wonder if the screws from said posts might line up with some of the grill slits on the base of the machine.
For those interested in keeping old machines faithful to their manufacturer I can happily report only Apple products (but for a bit of solder and hot glue) were used in this speaker upgrade... Even the wire was pulled out of an old Apple serial lead and then delightfully plaited by yours truly. Further photos of the install to follow.
Electron, apple iie platinum, BBC, colocovision. Your office is as organised as mine...
... office :)
im planning a wedge under the keyboard too, I'll respond with pics if the cheapo speakers I ordered fit, there's a tiny gap, prob too small but I'll try.
Biggest issue is the slot as my z80 card is in 4. Will overcome somehow!
Cheers!
Good spotting on the computer front, but there's two more lurking... ;)Quote:
Originally Posted by iainjh
Soldering and instructions made sense?
FWIW: Mockingboards will work in any slot, it's just not all software that supports them either auto-detects or asks. The default assumption is slot 4.
Have fun!
Instructions look a-ok thanks!
And it arrived yesterday, I just hadn't noticed the post. Thanks again Charlie, I'll get to it in the next days and will report back
Time, I feel, for some installation photos.
First off lets's get those internal speakers sorted:
In the end I decided to cut down the plastic from the set of speakers I butchered further up the thread to make a slightly neater installation. Also I used a fine old trick to make some damped stand-offs for mounting them to the chassis. Too many vibrations going trough the base plate of the computer might result in some rattling... Take a hot glue stick and cut it in to a number of appropriate lengths, then use some melted hot glue to attach said lengths to the plastic. In this case six pieces. Next stand the speaker board on it's feet in position and slide a hot knife between each leg and the base of the computer. This procedure:
Melts the end of the glue stick, so attaching it to the surface.
Allows one to adjust leg lengths as required.
Gives the speakers some vibration damping attachment.
I then ran the plaited left and right channel wires under the motherboard to poke up in the region of slot 4. The other end is attached to a stereo potentiometer for internal volume control. This was mounted through a drilled knock out on the back of the machine. There's a sticky label under the pot to reduce the chances of a short with the metal case. For info I'd say a 5k pot is more than enough, stereo, and preferably logarithmic.
The photo above shows how I wired the pot up: Pin header takes left and right audio from the amplified output on the board to the pot. The grounds are wired to the left most pins and to their respective outside headers on the output side. The left and right lines are each soldered to the middle pins of the pot, and the two middle pins of the output header soldered to the two rightmost pins on the potentiometer. Grounds are therefore wired straight through, but left and right go through the pot.
At this point I decided to make a production board of my own to stay in the computer. I'll keep the socked board for testing ICs.
Here's my semi-built production board showing some hopefully useful suggestions: The motherboard audio in cable was taken from the Apple's now redundant speaker and soldered directly to the IC side of the board. The reason being for added security; once an IC is soldered over it it's unlikely to come free. Note: If this cable is attached the wrong way round audio pass-through won't work! No harm done, it's easiest to to swap the pins round on the motherboard header end.
It's really very important to solder in the Amplifier Module's pins before soldering in any ICs, BUT then solder in the ICs before soldering the Amplifier Module.
Also there's no harm in attaching the 3.5mm audio header to some short lengths of wire (twisted), so allowing it to be mounted to another knock-out rather than necessitate grovelling about inside the computer when you need it.
As it happens I've run out of PAM8403 Amplifier Modules... I bought loads but must have used more than I realised on my dud boards. So my production board has no internal out at the mo'. Never mind, it works fine plumbed via the line out to my monitor's speakers and I have more on order.
PS:
Very neat. Inc lots of USB sockets... for the pi?
i will get to mine soon I promise! Need to receive my speakers and measure up. Thanks also for the new pics which are always useful.
Yes, USB , RJ45, and HDMI ports from the Pi. ;)
Oo, oo...
Don't hold your breath because I tried this before and failed, but I never could work out why the Mockingboard used two 6522s when the only important difference in their wiring was which 6522 and AY chips were active: one 6522 to each AY... why not use one 6522 and activate the AY chips directly?
So in the interests of neatness (maybe OCD) I've come up with a design that uses one fewer 6522s. If it actually works there's a few pennies saved, a bit less soldering, and a slightly less cramped layout. I've also noted my version of this board is bl**dy picky as to what type of 7404 IC is used, I guess there's some timing right on the edge... I may trial using a 7400 (NAND) as an inverter in the hope of achieving some extra robustness and a few more pennies off the cost. I guess I could generate my own clock instead of stealing one from the computer but that's more components. If a 7400 proves a better choice that will probably see the end of the activity LED... tbh I only included that because the 7404 had a couple of spare gates.
Anyway, the .zip below contains the Eagle files for this version. If it looks like it will work I might order a few boards as I'm very nearly out of Mk4 boards. Feel free to make comments.
Awesome work my friend, my only concern is the volume control being on the speaker outs...
this will upset and change the loading on the Amp module and 5v supply.
Volume pot needs to be inline with the inputs going to the Amp module.
:)
Thanks for the feedback, I shall do a bit of jiggling and post an update...
If there's a frustration it's one can't rely on where the slot cut-outs will be. I'd like to give the option to mount stuff on the board that lines up with the back of the computer, but I think it's going to have to continue to be wires.
Another update:
This time a proper header for volume control on the internal header, placed in circuit before the amplifier. I feel another order to Seeed coming on... 'nervous that I haven't understood the implications of removing a 6522 properly and I get another batch of coasters. Fingers crossed.
Yet another update:
Primary board has grown a little bigger to allow easier placing / soldering of components, hence name change.
Addition of buffering IC to help stabilise Apple bus.
3.5mm socket and volume adjustment now on separate (snappable) board for easier mounting.
System and MockingBird audio mixing now adjustable via a trim pot.
Holes added near audio in/out headers for cable management / strain relief.
Thoughts / suggestions most welcome. If anyone feels like doing a sanity check to help ensure I've not made any stupid mistakes I'd be grateful. :)
PS
I've neatened up the schematics and boards a bit since posting this link. Primarily thicker GND and VCC lines and some slightly neater routing in places. Also added option for further decoupling cap on the 7404, but otherwise no functional changes. Did I set up the buffer IC properly? Should be A to B pins and no blocking...
Last Update:
...maybe.
I guess there's something I don't understand, or at least I'm aware that I don't understand something from among the vast array of things I'm entirely unaware of...
I'd swear the Mockingboard design could get away with just one 6522 rather than two by offloading chip select duties on to the two AY 8913s, I'm always keen to make things as efficient as possible. Sadly, while I can get it to work, I can't get it to work reliably in all situations. Bum!
So two 6522s and two AYs it is then. On advise I've added a 74LS245 to buffer the bus, a trim pot to allow adjustment of system and sound card mixing, and given the components a bit more room. I've made extensive use of GND and VCC fills, not apparent in the photos. Also 3.5mm audio connector and volume control devolved to a daughter card for a more professional result... oh, and I put the volume control in the right place this time. As a result the card's grown a bit so I think MockingBird and Egg would be more appropriate names:
The two are to be joined by a 10 way ribbon cable. It could have been smaller but some duplication of signals was needed as the Egg itself can be cracked in two should separate mounting of audio port and volume control be desired.
I'll probably order some PCBs to test in a bit. Comments / suggestions are most welcome.
Just beautiful my friend, Someone is writing a .mid to mockingbird Convertor ;)
:)
blush: Thank you, and both excellent and intriguing news.Quote:
Originally Posted by TheCorfiot
I need to go though the audio lines one last time to be sure I haven't gotten any of my wires crossed, and reread the 245's data sheet to be absolutely sure I set it up right, but do you feel time I sent off the Gerbers for a test run?
Thanks again for the kind comments / helpful advice.
PS
Yamaha do some interesting AY compatible ICs:
https://en.wikipedia.org/wiki/Genera...ment_AY-3-8910
I was going to base the card on the YMZ284 but couldn't find any at a sensible price... The YMZ285 could be very interesting indeed with regard to MIDI and other stuff, assuming it can be found at a sensible price and I find the datasheet. ;)
PS
I have to say this PCB designing lark can make one very paranoid, and a tad frustrated...
Last night I thought I'd have one more run through both boards before generating the Gerbers for manufacture of prototypes. I couldn't help but fiddle with the daughter card to make it nicer but judged the MockingBird itself "good" but for the addition of a logo... but I though I'd take one more look at the schematic: Blast! I'd forgotten to hook up one of the data lines between the left 6522 and AY ic's...
...much paranoid checking didn't throw up any other errors so I went back to the board to insert the missing line, but d*mn me if I couldn't see a way to route it in!
So, back down to the power line level, reroute the whole bl**dy thing again and now I've got some hopefully good designs to send to Seeed.
FWIW:
I'm a self taught rank amuter when it comes to using Eagle but I'll quickly run through the process I use in case it helps others.
1) Design the schematic in Eagle trying hard to keep things neat and use the absolute minimum of wired connections. Much better to label all the pins with something sensible and use those labels to make connections. That way the schematic has some chance of being legible and is much, much easier to alter.
2) Open a board for said schematic and place the ICs in something approaching a logical arrangement while attempting to keep the "rats nest" of connections looking as "nice" as possible. Place passive components with attention to making positioning neat and logical while also trying to ensure you're not adding too much complication to said "rats nest". Attention here will make routing much easier later.
3) I find Eagle does a pretty good job auto-routing but tends to make power lines unnecessarily complex. As it's nice to have extensive power and ground planes I tend to route these myself, power on the front and GND on the back. Again attention to neatness, while balancing the shortest runs but trying to keep to the edges of the board. The latter will help routing the rest of the lines. I also tend to at least double the default line width using the change icon when routing power lines. I tend to add / route power rail smoothing caps and any IC decoupling caps myself as Eagle seems only to put them in electrically sensible positions rather than on the power inputs / next to the desired ICs.
4) I then usually get Eagle to auto-route the rest using "maximum" effort settings. It's then a case of picking the neatest result from the presented options that make it to 100%. Once selected it's worth looking at the result in detail, where there's room I try to give more room to any lines where Eagle has jammed them a bit close and neaten up any stupid / ugly routing.
5) At this point I use the draw, polygon function to draw two boxes tightly round the whole PCB. Assuming the gnd is routed on the back and power on the front I select each box in turn (right click, properties) to put one on the top and one on the bottom, and fill 0.016 in to the spacing box to be sure the fill doesn't get too close to the traces. Right click on the bottom polygon, choose name, and type gnd... Eagle will ask if you want it connecting to GND, say yes. Do the same with the top poly but call it vcc. If you then select tools, ratsnest Eagle will fill you two nice power and gnd planes covering most of the board.
6) I usually go through step 5) again, but this time not renaming the 3rd and 4th polygons to fill any remaining gaps... pointless but neater.
Eagle can be set to auto select trace width via the schematic but as I do the power/gnd lines myself I don't find it useful. Also you can do the power/gnd polygons before routing so, in theory, these are done automagicaly. Having said that I find Eagle tends to make a right Horlicks of this and takes an absolute age to route... even with 8 cores going at 4.5Ghz.
Right, time to go knocking on Seeed's door and see what other mistakes I've made.
I realise I'm probably the only one interested in this but while waiting on Seeed to send me my V2 boards I couldn't help but fiddle a little more with the design:
Basically the same as before but with added separate headers for each of the AY's three voices, a 5v header, and a 12v header. Why? Because I could, but also because I came across another elcheapo mini amplifier stereo module that will give about 15w per channel at 12v (OEP30W). This gave me the idea for an add on board, and that would need the extra headers...
Will anyone but me want this? Probably not, but I'm looking forward to six channels of Line Out or a thoroughly amplified six speaker set up inside my Apple II, assuming the PSU doesn't give up entirely. :blink:
Attachment 127428
Here's one for you Charles ;)
Ooo, thanks very much. :cool:Quote:
Originally Posted by TheCorfiot
I think I need to get out more. While waiting on my latest boards to arrive I couldn't help but fiddle further with the design:
Hmm... Eagle's latest update seems to have hidden / gotten rid of the Export Image function, still I can take a screen shot. If there's actually anybody wondering what the latest iteration is about I've been looking in to the various updates Yamaha produced for the AY series of sound chips usually used in the Mockingboard design...
...There's a few very interesting possibilities, some of which don't seem to available or have a data-sheet. One or two also don't carry full AY compatibility, which brings us to the YM2413. As near as I can tell it's AY compatible, and available in numbers at a sensible price. It comes in a smaller package than even the AY-3-8913 I've been using and comes with 16 voices of FM synthesis!
All being well I'll hack one of my current boards to test, and if it works I'll have have full Mockingboard compatibility with improved sound quality over the AY chips and be able to produce some really decent FM output to boot. See link to most interesting web page, examples at bottom: http://www.waveguide.se/?article=the-ym2413-fm-opll
...I had a small hiccup with my IIe: The keyboard started going bananas with the auto-repeat. Happily it turned out just to be a bad C71 and replacing it fixed the issue. I found a really useful problem solving .pdf for the Apple II, if anyone wants a link let me know.
Normal service:
Attachment 128058Attachment 128057So here's the (nearly) final-final version of the AY-3-8913 MockingBird. I can report it works perfectly, and the port mounting solution fits exactly as intended - genuinely surprised by that as I did the measuring using "#1 eyeball". I even seem to have picked the right volume control pot for it: *Edit* 2k, not 5k *Edit*, non-linear. The sharp-eyed will spot a 3k resistor in place of a System Sound - MockingBoard mixer pot, that's just because I currently don't have any and 3k seems to work well. I also seem to have run out of 6522's, spot the ancient MOS one I dug out of somewhere... *cough*
MockingBird V2c and Egg
Attachment 128056Attachment 128055
Installed and Back Panel
Why (nearly) final-final? Well, this is my V2c board but I've done a V3 in Eagle. The latter is functionally identical but has the IC's placed in a more pleasing arrangement, and also comes in a Yamaha flavour too... I need to do a mock-up of the latter when my YM IC's finally arrive to be sure it works.
So very nearly ready to go in to proper production: The Mockingboard is (nearly) available once again, an shouldn't be at the usual eye-watering price even retro Apple kit seems to go for. :)
That Looks so much Better, Really like it
If you have a spare board I would love to transfer the components over from the prototype and use it as is my friend.
Congratulations
;)
Thank you, and of course. :-)Quote:
Originally Posted by TheCorfiot
*Edit again*
For info I've taken to soldering the amp module direct the the board without any issues. Specifics:
-Sticky label on back of module (not covering the pin holes) to prevent any (small) risk of shorts with the main PCB
-Fill one of the pads on the Mockingbird PCB with solder and the same for the equivalent pad on the Amp module
-Place Amp module carefully in position and apply soldering iron to previously filled pad
(the two pads will melt and weld together)
-Repeat the process for the rest of the pads
-Check continuuity
Call me silly for not considering this before, but this is much neater / more convenient than using headers to attach the two as I did before.
..may well be wanting one of these myself Charlie ..but got to get my recently purchased IIe fixed and returned to me first ..
The parcel was collected today ..and returned to vendor ..
Hopefully good news in the future..
What kind of 'bucks' will we looking at for a mockingchick ?
rgds
VS
Hello,Quote:
Originally Posted by ViperSan
I'm sure I can scare one up for you when you're ready. On the subject AmiBay has some rules with regard to buying / selling procedure. So if / when we come to that point I guess I'll need to post one for sale on the relevant forum for you to officially express an interest in.
To any mods who are reading (yes, I know I was one once but I've got a memory like a sieve): Am I about right with the above reply? Thanks.
Thanks Charlie ..
Sadly that may be a while off yet ..
You know I recently purchased my IIe ??
..and that it had issues ..
well ..
the vendor asked me to return it in order that he might fix it.
I packed it up and did just that.. parcel force damaged it in transit ..
I'll attach a couple of pics to show what was done..
The vendor was most appologetic and is seeking compensation...and in the meantime has offered a full refund if I want it.
OR ..he is expecting another 2 weeks from the incident ..and my name would be on it ..plus he will also bundle some free software to compensate me for the distress and wait.
I agreed to the latter..having spoken at length to him on the phone.
He is genuinely upset about this ..and understandably so.
I'm sorry to invade your thread with this..but thought you might be interested in the saga..
sounds like he is getting another apple for you? is it a us one? you mentioned having colour in previous thread i thought.