hack. it. up.

March 19, 2012

In order to illustrate what was involved in getting the information together for getting PR8 and Pulsar running on hardware I thought I’d document the whole process here including some pics of some of the boards I created to perform testing and some notes on some experiments that didn’t work out in the end :)

01 – How do you get a program running on the Famicom?
The most important thing you have to understand about the Famicom and the NES in general is that everything is driven by Mappers. Mappers are memory and hardware management chips which allow the Famicom to extend its bespoke capabilities to address more memory or extend graphics or sound or SRAM saving capabilities. For more on mappers in detail check here: http://en.wikipedia.org/wiki/Memory_Management_Controller

Where it gets tricky is when there are subsets of Mappers that people don’t know an awful lot about – these include strange board revisions that may have extended VRAM or WRAM capabilities – increasing the amount of addressable SRAM saving or even removing said abilities (more on that later)

In the case of NTRQ it was relatively easy to create a hardware cartridge solution for running the program as it ran on a standard SNROM layout and MMC1 mapper chip configuration, using a PRG rom and CHR memory ram to store gfx data… So creating a dev cart for this nice music tracker just involved swapping out the PRG rom data on the correct board and wiring it up following the slightly different mask rom pinout NIN used on their Famicom and NES boards, see http://hackitup.tumblr.com/post/15291113007/creating-a-ntrq-cartridge-for-the-famicom for more information.

However in the case of Pulsar and PR8 the board layout and Mapper called for the incredibly rare SXROM MMC1 variant – used only on two Famicom titles to my knowledge (Final Fantasy I+II and an obscure baseball game). SXROM further extended the MMC1 mapper layout to allow for:

1. 8kb of CHR RAM

2. 32kb of SRAM

3. 512kb of PRG ROM

The only problem was that obviously in order to get it running you would need a donor cart with the correct board layout and memory capability – the easiest way to get this going was to grab a FF1+2 cartridge of ebay…

02 – Creating a FF1+2 SXROM devcart
Once FF1+2 arrived I was able to de-solder the PRG rom and insert a socket into its place and pop PR8 into the cart and getting it running:

FF1+2 Devcart

Also in order to get the actual cartridge into the system and be able to probe it correctly (due to the size restriction of the cart port) I had to create a dev tower out of a NES/Famicom + and Famicom/NES converter I had to hand:

Dev Tower

However at this point it turned out that the way that real Famicom hardware behaved VS something like the Powerpack or even the NES was different.

I tested the dev cart plugged into one of the test Famicom’s out of its casing (to avoid the cart slot issue) just in case the dev-tower was causing some sort of delay/incompatibility (just in case) but it was still behaving erratically – with boot up issues.

My thoughts on this: On Powerpack the Famicom’s ram data is initialised slower than on h/w – this can create problems if you are testing things on this platform – as when moving it to real cartridge h/w you might see boot up glitches on your software that only correct themselves after reset.

On the NES itself the power button seems to supply power in a slightly different way to the console – possibly creating a smoother boot up process – the Famicom is a flipping switch whereas the NES is a pushbutton which seems to supply power more gracefully to the unit.

Both these issues were causing PR8 + Pulsar to behave erratically on bootup on the Famicom vs the NES + Powerpack, after speaking to Neil and trying out a few different test versions on the dev-cart he nailed the problem by fixing the initialisation routine and inserting various delays and we were all good :)

Once it was clear they were behaving correctly on hardware (after testing both programs to -death- on the FF1+2 based devcart) it was time to move onto trying to reverse engineer the SXROM format and layout and try and convert a SNROM (a very common boardtype – and the same type of board that NTRQ runs on) based cartridge to run the software reliably.

03 – Creating a SNROM SXROM Frankenstien Devcart
The next step was to try and get these nice programs running on cartridges that people could actually get their hands on (and frankly it felt terribly wrong butchering FF1+2 :)

I ordered a bunch of SNROM based Famicom carts off of good ole’ ebay and waited for them to arrive. Which took bloody ages – so while I was waiting I did a ridiculous amount of reading up on the various chips that sat on the FF1+2 cart.

It had a 62256 SRAM chip supplying the 32kb of SRAM to the unit, this was keyed via a hex inverter due to the MMC chip supplying a high signal to CS…

I traced out what connections were going where on the board and with some decent pinouts from nesdev on the MMC1 chip I was able to see where on earth the SXrom board was sending its SRAM data to/from etc.

I grabbed some Hyundai 62256B sram chips off ebay and some Toshiba TC51832SPL-85 skinny sram which shared the same pinout (more on that later *Grin*) as the SNROM boards actually have thru holes for skinny sram too! I also had various hex inverters and hex buffers laying around…

Once the SNROM carts finally arrived I constructed the following little beastie in stages for testing:

SXRom SNROM Devcart 01

SNROM SXROM devcart 02

SXROM SNROM Devcart in Famicom

After wiring it all up it worked – almost – but unfortunately the SRAM saving was half working – instruments were saving but pattern data was not, I tracked this down to where I was powering the hex inverter on the board (I was grabbing power from the MMC1 chip – don’t do this – as it seems this does not yield happy results :) so moving the hex inverter power and gnd lines to the sram chip itself cured this (which I should have done from the beginning thinking about it logically *Grin*)

After it was all done I popped it in a nice cart case and printed a label:

PR8 Famicom Cart

Things that didnt work out along the way

Anyone that claims that things just work when doing this sort of project is lying :) - here’s a couple of example of some experiments that didn’t check out in the end;

1. TC51832SPL-85 skinny ‘sram’ does not work, as it is not true SRAM and requires a different sort of powering to retain data reliably - don’t use it :O) - you’ll have a working board but utterly unreliable saving and storage will disappear over time, even though its pinout is compatible with the 62256 this is a shame as it can be wonderfully cheap :)

2. NES Open Golf (and possibly Famicom Mario Open Golf) cartridge board layouts seem to differ from other MMC1 SNROM boards - presenting issues on bootup with both NTRQ and PR8… very strange + havent had time to track back what’s going on here… thanks to RG for doing a lot of testing on this board too!

More information

Read instructions on how to build one yourself here:

http://hackitup.tumblr.com/post/19201730531/turning-a-snrom-famicom-cartridge-into-sxrom-to-run

You can get a nice Famicom label for PR8 and NTRQ I made here too in pdf format for easy printing:

http://hackitup.tumblr.com/post/19368549455/pdf-famicom-labels-for-ntrq-pr8

Please note I’d like to thank the nesdev and nes cart db sites for being an invaluable resource in investigating and nailing what exactly is going on with the SNROM + SXROM board+layout types and Neil for making the ace software :), hope you enjoyed the read

\o_

Please Note: If you have enjoyed reading my ramblings or you are building or using one of these carts - please do consider making a donation to any of the following charities, many thanks <3

http://supportus.cancerresearchuk.org/donate/

http://england.shelter.org.uk/donate

http://www.unicef.org.uk/Donate/Donate-Now/

8:15am | URL: http://tmblr.co/ZfgeKyIETIOU

(Notes: 1)

March 15, 2012

PDF Famicom Labels for NTRQ & PR8

PR8 Label

Just popped up some Famicom labels (will print at correct size - just round the edges :) for NTRQ and PR8 - grab them here

7:43pm | URL: http://tmblr.co/ZfgeKyI2T9nF

(Notes: 1)

March 12, 2012

Turning a SNROM Famicom Cartridge into SXROM to run PR8/Pulsar

In order for you to run the rather lovely new music software that Neil Baldwin has created for the NES / Famicom on real hardware it was necessary to either sacrifice a Final Fantasy I+II cartridge or buy an rather expensive CF cartridge – here’s how to do it using a normal SNROM cart – (which is exactly the same cart type I got NTRQ running on earlier on this blog, check that guide for info on some donor cartridges etc…) please bear in mind this is a tad more involved than simply burning an EPROM and bending up a few pins :)

Shopping List

1. 62256B SRAM IC (32kb) x1 (I used a Hyundai one)

2. HCF40106B Schmitt Trigger Hex Inverter IC x1

3. Wrapping Wire (Kynar is best)

4. 27c020 EPROM 256kb x1

5. + Grab the program data from www.nes-audio.com

Instructions

First of all follow my guide to getting NTRQ on a cart below – this will prep your cartridge for the EPROM and connect up the necessary pins to the board in the correct way, please only use 27c020 eprom’s for this and double up the data for PR8 or Pulsar by using the following command line:

copy /b romname.prg+romname.prg romname256.prg

After you have done this I recommend you have a nice hot cup of tea. :)

Replacing the SRAM

After you have got the EPROM soldered into the board we need to move onto replacing the 8kb SRAM which is located above the PRG rom on the SNROM Famicom board…

Once this is removed the next step is to prep your replacement 32kb SRAM chip for the board…

Bend up pins: 1, 20 and 26

Solder the SRAM chip to your Famicom board on the underside and topside

Next we are going to connect the SRAM to the MMC chip

1. Connect pin #1 of the SRAM chip to PIN #10 of the MMC1 chip on the underside of the SNROM board

2. Connect pin #26 of the SRAM chip to PIN #9 of the MMC1 chip on the underside of the SNROM board

Generating a correct /CS signal

Next we are going to prep the Hex inverter – bend up pins 1, 2, 7, 14 – snip all other legs as you will not need them…

Now we are going to connect our Hex inverter to the board

1. Connect Pin #1 of the Hex Inverter to MMC1 pin #6 on the underside of the SNROM board

2. Connect Pin #2 of the Hex Inverter to SRAM pin #20 which you bent up earlier

3. Connect Pin #14 (VDD) of the Hex Inverter to SRAM pin #28 on the underside of the SNROM board

4. Connect Pin #7 (VSS) of the Hex Inverter to SRAM pin #14 on the underside of the SNROM board

As long as everything is soldered in correctly you now have a fully functional SXROM board which is now running PR8 or Pulsar depending on what you burnt onto your EPROM

Diagram

Here’s a little diagram of the wiring - please read the guide thoroughly alongside it :)

Notes

It is worth noting that you might want to glue your Hex inverter to the back or top of the board out of the way – it should all just about fit into the original cart case :O)

Just a little note about something I forgot to mention - when you first solder the SRAM in place on the board and get it all running you will need to reset PR8 and “Clear ALL” in the Clear data submenu - as it’s more than likely you’ll have some bizarro instruments etc in SRAM at first bootup (especially if you’ve been testing/re-soldering connections) - after that the cart will just work :)

Happy drumming / tracking + thanks to Neil for making such an ace bit of software on an brill old machine… as before don’t you dare profit off of this, I’ve spent about 7hrs of my spare time today reverse engineering this + the SXROM board so people can do this cheaply and if people start charging 50£ for them I shall be a tad cheesed off :P

FYI the total build cost is:

SRAM: 2£ tops
Hex Inverter: 50p tops
EPROM: 1.50£ tops
Donor board: 4£ tops

Also it would be nice to hear from peeps that have got this running – do post on the thread on http://chipmusic.org/forums/post/93904/ :)

Quick NES Related note; as a general rule if you are going to attempt these guides on the NES rather than the Famicom you generally have to solder each and every pin of the EPROM on both sides as the layout is more tricky on NES SNROM boards! Also for the sake of reliability use only 27c020 EPROMS for these guides – not 27c010 as people have reported problems with those :O)

Please Note: If you have enjoyed reading my ramblings or you are building or using one of these carts - please do consider making a donation to any of the following charities, many thanks <3

http://supportus.cancerresearchuk.org/donate/

http://england.shelter.org.uk/donate

http://www.unicef.org.uk/Donate/Donate-Now/

6:46pm | URL: http://tmblr.co/ZfgeKyHuWoVZ

(Notes: 2)

March 12, 2012

‘Sequencing’ the unmodded Gakken SX-150 Using only audio input

Just got my SX-150 thru the post and was surprised nobody had looked into how exactly the EXT-SRC input worked on the device; short of it having a GND that you can hook upto for taking over CV input on the stylus. Knowing that Gakken’s Theremin can be used as input device via this socket I set about having a bit of an experimental session sticking various waveforms thru the EXT-SRC via the soundcard to see if anything yielded a sound from the unit.

After doing a bit of testing via a tracker drawing various single cycle waveforms and shifting the pitch into ear bleeding territory, my best guess was that the input was some sort of simple logic input – so I started experimenting with different hz of Squarewave outputted from the expression evaluator in Goldwave… A square wave at around 5000hz with a volume set at around -3.2dB yields a constant tone from the synthesizer with no stylus input which was interesting – shifting said waveform down in volume in .5 or .10 dB steps affects the pitch of the wave which is also useful… So armed with this information it was pretty easy to create some simple looping waveforms at the correct hz and volume to start to control sequencing simple dirty baselines with nothing other than a simple phono to phono cable connected from the computer side to EXT-SRC on the Gakken-SX150 :)

Things to bear in mind

1. as we are definitely not inputting exactly correct waveform data into the device the actual baselines are not tuned in a conventional sense but still sound pretty fat, more experimentation by someone else would probably yield more information (I have no time *grin* :)

2. using the stylus at the same time allows you to hold the pitch at a note and have the input modulate or affect the waveform around the inputted note which creates rather nice samples too

3. make sure your editor / dAW is set to maximum volume + hard pan your entire monophonic ‘baseline’ to the LEFT including all samples you create for inputting notes

4. Any baseline you create should be made up of the individual noises you have outputted from whatever wave generator you are using but feel free to experiment with changing the pitch of individual sounds to make interesting sh*t-shot sounds *grin*

5. Try a squarerwave at 6000hz as well for ‘octave up’ :)

6. Try FM modulated sounds for interesting effects into EXT-SRC

7. Try extremely highpitched modulated random noise into EXT-SRC for really interesting sounds

8. Try shifting the octave of your sequence up and down to see how this affects the synths output

9. Don’t play back your sequenced waveform in your editor without your Gakken-SX150 connected as it will hurt your ears and probably your speakers *grin*

10. Popping a simple Lowpass filter over your sequence will yield interesting results

Thoughts

It should be relatively simple for someone to create a simple sequencer based on what I’ve discovered to control the thing from software on the computer side :)

Hear it here: http://soundcloud.com/andy_l/seq-the-sx-150-using-audio

Check out the SX-150 here

http://www.makershed.com/product_p/mkgk8.htm

http://www.juno.co.uk/products/gakken-analog-synthesizer-sx-150-synthesizer/351909-01/

5:55pm | URL: http://tmblr.co/ZfgeKyHuKeR8

January 4, 2012

Creating a NTRQ cartridge for the Famicom

What you need:

· An Eprom burner capable of writing 27c010 or 27c1001 eproms

· A Solder sucker

· A Soldering Iron (Temperature Controlled will make your life easier)

· Solder (Lead 60/Tin 40) Using leadfree in this instance will cause you pain.

· Pliers (small!) or heat proof tweezers

· Flathead screwdriver

· Kynar Wire (it’s nice and thin and perfect for doing this sort of thing)

· Micro Flathead screwdriver

The first thing you need to do is find a suitable donor cart – anything with the board code HVC-SNROM (more info here: http://bootgod.dyndns.org:7777/search.php?unif=HVC-SNROM) will do the trick.

I used Takeda Shingen 2 as my donor cart for this one, it’s a baffling mah-jong/strategy game which seems very common in Japan so no terrible loss to the world *grin*

Once you have your cart, preheat your soldering iron at a medium temperature – then you need to get the cart open.

Opening the Cart

Famicom carts are a pain in the arse to get into but one method I’ve found for getting them open safely is to use a micro-flat head screwdriver and slightly open the bottom of the cartridge with your fingers and get the flat head in between the two halves at the base (side!) of the cart, just where the indent for the eject mech of the Famicom is:

< here

When you have your screwdriver inserted, GENTLY twist until it begins to come apart, you may hear a snap, unfortunately before you get good at this you are going to snap a few internal clips – but it’s VERY easy to simply glue the two halves of the cart together if you are making a permanent cartridge… or you can just use the board bare in your Famicom (see further in the guide for an important note on this)…

Okay you have the board out, it should look like this:

Special thanks for the cart pics to NES Cart dB!

The chip you want to remove is U1 PRG. DO NOT TOUCH the other chips, they are important… :)

De-soldering

Turn the board over and begin heating pins/solder on the bottom of the PRG chip…

· As you heat the pins pay attention to the solder, once it begins to become runny – move your solder-sucker over the iron and the solder area and suck.

· The solder will come away, don’t worry keep at it – you will get the hang of it, it’s all about timing and getting it just hot enough ;)

· Always shake the solder sucker dry of any excess dross/solder after sucking a connection dry – a full solder sucker is a badly performing solder sucker (giving it a helpful tap with a screwdriver on its side is a good way of dislodging pesky sucked solder)

· Once you have de-soldered the back-side of the board you need to move to the front. This is the painful part;

· Unless you have a de-solder station – you will now have to clip each and every pin leg of the PRG chip as closeto the central (black) part of the chip as you can.

· You need to leave enough leg to allow for easy removal from the board as you desolder on the front side (90% of NES/Famicom boards are soldered on both sides of the board for each chip).

· Once you have clipped the chip off you should be left with a lot of chip legs sticking up off the front side of the board.

· Simply heat each leg gently with your iron whilst tugging on the leg with a small pair of pliers and they will easily come away leaving you with an empty PRG slot.

· You will now need to clear each chip hole individually with your solder sucker so you can see thru the holes in the board to the other side clearly as we will want to be popping in a fresh EPROM chip…

Burning the Rom

Once the board is clear in the PRG area you will need to burn your EPROM chip:

· You will also need to split the NTRQ_NTSC.nes rom into its PRG part (removing the ines header) just use Ucon64 (available at http://ucon64.sourceforge.net/ ) with the –s command:

· Ucon64 –s NTRQ_NTSC.NES

· This will give you a nice raw .PRG file. This is what you need to burn onto your EPROM.

· Use your EPROM burning software and select the type of EPROM you are using… (You should be using a 27c010 or compatible EPROM chip)

NOTE: Bear in mind that 27c010 and 27c1001 chips are identical in all but name… A 27c010 eprom has 128k of space on it which is handy as its just right for popping NTRQ on J

· Okay set your EPROM burner burning/blowing the .PRG image in BINARY mode and make yourself a nice hot cup of tea.

· Drink Tea.

Prepping the Chip

Once your EPROM is burnt you need to do the following to the Chip:

· Bend up legs 1, 2, 24, 30, 31

· Clip down the bent up legs leaving only their chunky stub (but enough to solder to)

· Tin with solder the following legs: 2, 24, 30, 31, 16 (the top part of this area – as this pin is still going into the board)

· Follow the above diagram and solder wires to bent up pins 24, 31, 30, 2

· Solder the wire from bent up chip leg 24 to Chip Leg 16 (remember chip leg 16 is going into the board later and is NOT bent up – we are getting GND from here)

· Solder the wire from bent up chip leg 31 to PCB thru hole 2 (IMPORTANT NOTE: pay attention to which side of the board the wire should be soldered to by checking where to the trace to that hole appears – if it is on the front solder the front side and vice versa… s

· Solder the wire from bent up chip leg 30 to PCB thru hole 1 (check the note above)

· Solder the wire from bent up chip leg 2 to PCB thru hole 24 (check the note above)

Inserting the Chip

Now once you have done this – pop your chip into the thru holes on the board.

NOTE: Pay attention that you have popped it in correctly – the board shows you the correct orientation for your chip; just look for the U indent at the top of the chip and match that to the board…

Now you need to solder it in on the back-side of the cart board:

· Solder all legs to the backside (except the bent up ones of course :)

· Turn the board over to the parts side, let it cool down a little and now solder all the pins closest to the cart connector on the EPROM on the front side carefully (that’s pins 17,18,19,20,21,22,23,25,26,27,28,29,32)

· Now solder pin 16 on the front side too, being careful not to break our wire to bent up pin 24

· Pop a little sticker over the EPROM window, anything that covers it is grand – I think I used a Doreamon one :P

Okay, let it cool down again.

Test it before doing the following… it needs to go in the Famicom parts side facing away from you! That means the battery is facing away from you :)

It should just work, if it doesn’t you have done a mistake – go back to the first soldering step and recheck your connections for bad soldering!

Once you are sure it is working we can start…

Putting it together

Next up you need to pop it into the cartridge case:

· Pop it open so you have 2 halves…

· The board only fits in one way and that is parts side facing away from the cart front label (it looks back to front but trust me - it just works like that… :)

· Once the cart is all back together (you might find you have to super glue a little on the edges to get it to stay together the first few times you do it) you might want to print out a nice label for it like this:

· Label dimensions for Famicom carts are:
Width 9cm, Height 4.3cm

Your done, go make some tunes on actual Famicom H/W peeps!

General TIPS

In order to get better output quality don’t forget to turn your Microphone on the P2 pad side on the Famicom down to Zero Volume, unless u want to shout out over your tune live of course, which does work hehe but you will have BG noize :D

If you are using the cartridge bare (ie without cart case round it) REMEMBER it goes into the Famicom with the parts side away from you, that is the back / underside of the board faces you if you are looking at the Famicom.

Build Cost:

The total build cost for one of these is about 6£ ish if you already have an EPROM burner:

1x 27c010 or 27c1001 EPROM – About 90p to £1.50 unless you are silly.

1x Donor cart – around 4£ including shipping (perhaps even cheaper if you are lucky)

Wire – 50p

Solder – 50p

Burner Info

You can get EPROM burners capable of blowing/burning these 27c010 chips from 20£ on ebay. USB variants from about 35£ do bear in mind that if you buy a cheaper burner it will most likely not support 16bit chips so if you are aiming to do chips for things like the MEGADRIVE or SNES or NEOGEO etc it is worth making the investment in a better burner like the GQ-4x USB series on your first purchase, after all who knows what else might come out on those systems in the future for our musical twisty fun *Grin*

EPROM Eraser Info

You can get cheap EPROM erasers if you plan on erasing / re-burning chips regularly from Ebay…

I got one of these ages ago for about 20quid to replace an older eraser that stopped working and it’s done a grand job dealing with all sorts of EPROMS (even 32mbit NeoGeo beasties) just make sure your EPROM windows are CLEAN so the UV light can get into the chip correctly :)

GUIDE NOTE: If I catch anyone selling this for profit after I went to the trouble of noting down how to do it and Neil spent bloody ages making the actual program - you will find my shoe heavily inserted into a place where the sun doth not shine :) Bear in mind it really only comes in at 6£ to make, even if you factor in labour then 15£ is the most anyone should ever charge for one of these!

Anyway I hope that helps some of you get some NES / Famicom music goodness out of your H/W – massive props to Neil for making the software it just rocks! Also thanks to NESDEV for pointers on nes PRG pinouts and generally being awesome too :)

That’s it! Happy New Year Peeps!

6:12am | URL: http://tmblr.co/ZfgeKyEFQzul

(Notes: 1)

January 4, 2012

Fixing dead Gameboy displays

Since I’ve finally got a few hours spare… thought I’d pop you all this lil’ tip from my workbench *grin*

If you have oodles of Gameboys with dead lines in the LCD, simply open up the worst one (make sure it is -powered off-) to try this out on:

1) Separate the screen part from the PCB so you have the LCD open with the ribbon cable hanging off it

2) Remove the foam bracer from the front of the screen

3) Get a normal cigarette lighter (a normal disposable one NOT A ZIPPO :D) set the flame to -low-

4) Light it

5) Apply heat to the ribbon connector underneath the LCD screen in swiping motions gently caressing the ribbon connector with the heat from the flame backwards and forwards -quickly- and -gently- for about 15 to 30seconds, paying attention not to overheat the actual LCD screen portion of the display (don’t worry if it discolours slightly it’ll recover its tone very quickly)

6) Pop foam bracer back in place

7) Stick GameBoy back together again

8) Working screen? If not it should be better - go back to step 1 and repeat paying attention to where the bad lines where when you tested it and giving that area more swipes with the heat but again, be gentle and fast!

Disclaimer:

I am not responsible for you screwing this up and breaking your Gameboy and please for the love of all that is ace be careful playing with fire.

I have personally fixed over 30 utterly busted Gameboy screens this way and I am talking -utterly- no display here, it’s a hell of a lot quicker than fixing it via prodding with a soldering iron which seems to be what other peeps are doing… Also as an aside - using heat (via heat gun or lighter or soldering iron) is quite a common fix for ribbon connectors in all sorts of H/W (especially keyboards/controllers) and I always wondered why no-one had posted anything on this here before so here ya go ^-^);

5:57am | URL: http://tmblr.co/ZfgeKyEFQ2TN

(Notes: 1)

January 31, 2011

hacking the NES & Famicom for split audio outs

Follow this simple diagram to add split audio outs to your NES or Famicom…

Open up your NES and disassemble it down until you have it sitting there on your work surface as a bare motherboard, locate chip 2a03 and check the following diagram:

Once you have done the mod, the NES/Famicom’s sound channels will output seperately on one jack split as follows:

Channels 1+2 will output from Jack 1
Channels 3+4+5 will output from Jack 2

Using a split Y cable to headphone jack plug you can record the NES’s sound into your computer now at a MUCH higher quality than before…

You will have to mix the audio down to Mono tho - as the NES is a MONO system… and the sound seperation is not natural… Unless you are playing back your own music of course and have taken advantage of this :)

You can also do this mod by soldering to the underside of the 2a03 chip, make sure you have the right solder points for the legs tho - I don’t want to be responsible for you frying your laptop by accidentally connecting something to +v :)

7:42pm | URL: http://tmblr.co/ZfgeKy2rADQH

(Notes: 1)

April 25, 2010

hacking the sega master system 2 #2

video/audio mods

One of the most annoying things about the SMS2 is that it only output’s a bloody awful RF signal to your TV - let’s do something about it :)

When you open up a console (or anything else that you are going to mod) it’s a good idea to check out what the IC’s (an IC is an integrated circuit) are that make up the board, check chips that are close to the video output for example if you are wanting to do a video mod, normally they’ll be a RGB video encoder sitting there that you can attach wires to or follow round the board to tap video / audio from…

So looking over the SMS2 board - you’ll (hopefully - unless your board is a very different revision) see a chip up near the top of the board with the following written on it: SONY CXA1145P: this is a REALLY common RGB video encoder made by Sony - it’s in tonnes of old machines… Doing a quick google on the chip ID will lead you to a datasheet - which tells you 3 things:

1) The chip outputs RGB (woot - we can wire up a RGB scart connector if we wanted to :)

2) The chip outputs Composite Video on pin 20

3) The chip outputs Audio on pin 9

We’re not worrying about 1) atm - but lets talk about Composite Video & Audio…

To do this you need:

1x 220uf Radial Capacitor

1x 75ohm resistor

2x RCA Jacks (a Yellow - for video and White - for audio would be nice :)

Simply wire up a connection from CXA1145P chip leg 20 to your 75ohm resistor, this in turn connects to the positive (see your capacitor for which side to solder to) side of the 220uf cap, the negative side of the Cap then links to a RCA jack.

To get audio out of the chip just tack a wire to Pin 9 and the other end to a RCA audio jack, do remember to ground your RCA jacks - checking the pinout for the Sony chip - you’ll see Pin 1 is GND

See the following diagram:

ne7-SMS2 Composite Output

4:18pm | URL: http://tmblr.co/ZfgeKyWjiGq

(Notes: 2)

Filed under: hacking sms2 master system 2 video and audio mods

April 25, 2010

hacking the sega master system 2 #1

language switch:

Slightly pointless but rather cool; you can fool the guts of the master system into thinking its a Japanese console.

Why would I want to do that you say? Well some games have different graphics depending on region (diff title screens, for example Power Strike is really Aleste in disguise :) and obv. go into Japanese language (useful if your learning Japanese or if you want to play the games in the original language for whatever reason) I’ve also heard talk that some games had differing levels of difficulty dependant on region settings but that info is a tad fuzzy :)

Anyway - onto the mod, it’s pretty darned easy. You need a single pole double throw switch (SPDT) and two bits of wire…

1) open your SMS and find the chip labelled: 315-5237

2) find the leg labelled 24 and count backwards 1. that’ll be chip leg 23 :)

3) solder a bit of wire to this leg, dont worry you dont even have to remove the leg from the board :)

4) in turn solder that to the middle (2nd) point on your switch

5) solder another bit of wire to point 3 on your switch

6) solder the other end of this wire to any point of the board that has GND (ground) your safe to leave the other point of the switch floating as that’ll be ‘dont do anything or off mode’ :)

7) a good GND point is just under the big 315-5237 chip there is a radial capacitor (thats the round one with the - - - -’s down one side… solder your GND wire to the side with the - - - symbols…

8) make a hole in the side of your SMS and whack the switch in

9) boot your console and stick one of your old SMS games (a good one is Wonderboy in Monsters Lair) into your console and boot up… Try the switch and restart - you should see the game boot up with the Sega Mark III bootup screen - then you’ve succeeded - well done

10) if you havent succeeded check your wiring :-)

11:16am | URL: http://tmblr.co/ZfgeKyWhOUY

Filed under: master sytem hacking language switch

April 25, 2010

greets :)

welcome to my little hacky hacky hack-a-hack electronics / customisation blog. enjoy.

10:50am | URL: http://tmblr.co/ZfgeKyWhC4R

(Notes: 1)

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