Welcome to the MegaCard Homepage!

What is it?

The MegaCard is the only expansion card you will ever need to install in your Amstrad MegaPC system.
It is a multifunction card specifically designed for the MegaPC and it's 1 free ISA slot limitation.


(click on pic for full size version)

Features include:

1. ALS100 sound controller chip providing SB/SBPRO/SB16 compatibility 2. real Yamaha OPL3 FM chip 3. Realtek 8019AS network controller providing a 10mbps ethernet connection and boot rom support for XT-IDE BIOS 4. scandoubler that makes possible for the onboard MegaDrive to output a standard VGA signal 5. an optional exclusive Serdaco MIDI daughterboard - the X3GS with a 16MB Roland-licensed GS soundbank (same core features as X2GS) 6. ISA header and MIDI I/O + routing configuration for the MPC010 PCMIDI MPU upgrade db

When the MegaCard is properly installed then:

you can use a normal 31khz VGA monitor for both PC and MD modes
the door switch for md/pc mode at the front will work same as before
the volume control slider will work same as before but only in MegaDrive mode , on
PC mode the ALS100 software mixer takes control like with all PC soundcards
the original Amstrad gameport will work same as before
you will only need to use the line-out jack on the MegaCard as it will also carry the MegaDrive sound output so
no external audio loopback cables or anything else is needed to get audio to your speakers
the scandoubler is a very fast design custom tailored to the amstrad md card with only 1 scanline delay - virtually 0 lag
there isn't any kind of resolution upscalling, output is the same resolution/refresh of the MegaDrive chip


You can read some more info or find more pics in this VOGONS thread.

How do you make the SEGA/Amstrad Mega PC even more mega? | The Mega Card video review by RMC - The Cave
the video also showcases the installation procedure so it's a must view for anyone installing a MegaCard



Installation Guide


WARNING: soldering required ahead so make sure you know what you are doing!
I will not be held responsible if you damage your system , you do this at your own risk!
Please be sure to read the whole section in order to understand how things work and then
proceed with the necessary soldering and installation of the MegaCard!

Remember that the RMC review video above contains installation footage - it is very
helpful combined with the information below.



First of all remove the blue jumper on the Amstrad megadrive card, it is for the "OPL2 IRQ SELECTION" and it
is completely useless even if you don't install the MegaCard. Nothing on PC world uses an IRQ for OPL2 and even
the original AdLib card does not have this functionality installed.



Next step are the 2 solder joints in order to connect the MegaDrive clock with the scandoubler section of
the MegaCard. These are 2 fairly easy points to solder , the connections are made on two of the pins of the big 53mhz
oscillator on the backside of the Amstrad MegaDrive card. Please look at the "clock cable connection" section of the
following photo and do the same with the clock cable you will find in your package:


(click on pic for full size version)

Make sure you solder the cable in the correct orientation. Once this cable is soldered correctly then connect it to the
MegaCard "clock connection" header and you are done! Please refer later to the instructions where connections are shown.



Optional 50/60hz switch installation:
On the above photo you can also see the optional 50/60hz switch solder point. With your card you have a small bag with those
optional components. Originally Amstrad soldered a patch wire in this section that forces the card to be in
English 50hz region for PAL countries. With the addition of a resistor and a signal wire using the switch at the back of the
MegaCard you can change between ENG-50hz and ENG-60hz modes on demand - even on the fly while the system is running.
It's basically the same as region modding a real MegaDrive console. So in order to do that you need to:

1. remove the original Amstrad link wire 2. install the provided 10K smd resistor in position R75 3. solder the provided signal cable on the spot shown in the photo - it is the same spot that the original Amstrad wire was soldered - PAYING EXTRA ATTENTION that it only connects to this spot and not shorting any nearby vias/components.

Please look at the above picture and do the same - this is precision soldering and you need to make sure that the signal wire
ONLY connects to the upper pad of R75 and nowhere else. If you want to lock the system to 60hz ENG region you can
omit the signal wire - adding R75 is enough to make the onboard MegaDrive run at 60hz instead of 50hz.



Optional disabling of the Amstrad OPL2 chip:
As you already know on the original Amstrad card there is an OPL2 chip that provides AdLib compatibility to the system.
Annoyingly the ALS100 drivers will always complain about AdLib port 388h being in use and will disable the OPL3
functionality on the MegaCard - this is also the case with win3x driver installation where some needed system.ini sections will not be
added. These "warnings" only occur during driver installation and when you run ALCONFIG.
You can always edit files afterwards and re-enable OPL3 - it will work just fine and the two OPL chips will co-exist
in the system without causing any damage or other issue. See the "Re-enabling the OPL3" section further below for more info.

For those that want to avoid all that and feel that the OPL2 is redundant after installing the MegaCard there is a way
to completely disable the OPL2 chip in hardware. But be warned the following modification requires some smd soldering
skills - so be sure you know what you are doing before you attempt this.

New easier way to disable onboard OPL2 1. locate U8 on the Amstrad MegaDrive card and solder together with a blob pins 5+6 (click on pic for full size version) 2. (optional) locate R34 on the backside of the Amstrad card and remove it (click on pic for full size version)

~ Old way ~ (still valid but a little more tricky to do) 1. locate U1 on the Amstrad MegaDrive card and it's pin #19 (click on pic for full size version) 2. lift pin #19 (click on pic for full size version) 3. connect lifted pin #19 to pin #20 - this disables the OPL2 on the ISA bus (click on pic for full size version)

This is the end of the soldering section :)



Jumpers, cable connections and general usage:


Here is a MegaCard overview with all the connector and jumper locations and explanations:


(click on pic for full size version)


For clock and 50/60hz switch connections please refer to this image:


(click on pic for full size version)

a. pay attention to the clock connection orientation so the scandoubler can work
(wrong orientation will not damage anything so don't worry)
b. the 50/60hz switch cable is both flexible and long so just route it like shown in the photos
(it's a ground signal so there are no interference concerns)


For the video cables connections please refer to this image:


(click on pic for full size version)

Connect the Amstrad MegaDrive card cable to the MegaCard and then use the included 20pin ribbon cable to
connect MegaCard to the motherboard header instead of the Amstrad card.
Notice how the 50/60hz switch cable is positioned - there is sufficient length to do the same.


Jumpers and general usage explanation:

You can enable/disable scanlines for the MegaDrive output with the corresponding jumper

If you use the md part in the stock 50hz md mode then make sure your VGA monitor supports 50hz,
all CRT monitors support it but some LCD panels do not like it so keep that in mind.

If scanlines are enabled then the "scanlines type" jumpers are active, they select the intensity of the scanlines.
There is no "correct" intensity - it's whatever you like best! All scanline related jumpers can be operated
while the system is running and results will be instantly visible.

ALS/EXP jumper block is only used if you have installed the optional PCMIDI expansion on MegaCard.
This block allows the user to select which MPU device controls a specific port so you can have a dual MPU setup.
If the jumper is put on pins 1+2 then ALS100 controls this port.
If the jumper is put on pins 2+3 then PCMIDI controls this port.

Amstrad MegaDrive card audio output is mixed internally in system and it's tied to the CD audio input of
ALS100 - so if you want to change this volume please adjust the "CD Volume" slider. No external audio
loopback cable is needed but the ALS100 driver must be loaded first so MegaDrive volume can pass through.

MIDI IN/OUT2 jack is a special jack that can be configured as a MIDI IN or OUT port , depending on
your needs. IN port is only available when the optional PCMIDI expansion is installed.
Refer to the jumpers image above on how to configure it by moving the 2 jumpers to IN or OUT position.

50/60hz switch will configure the MegaDrive part either as a 50hz ENG PAL or 60hz ENG region system.
Amstrad default is PAL region with the switch pressed. Region switching can be made on the fly - some PAL 50hz optimized
games might display glitches when switched to 60hz but it's only because they rely on 50hz timer to sync things.
For the few such PAL-optimized games that exist you need the correct 50 or 60hz region game to have optimal results.

Realtek RTL8019 network chip can be either configured via eeprom or jumpers. Default is eeprom configuration
so the card gets assigned port 280h, IRQ11 and a 16kb rom space for the XT-IDE BIOS. These settings are perfect
for the 386sx MegaPC motherboard and there is no need for them to be changed.
Eeprom settings can be altered with RSET8019.EXE program that is part of the chip's DOS drivers
Jumper settings can be configured according to the tables silkscreened at the back of MegaCard.

XT-IDE BIOS is used to overcome the 540MB HDD limit the Amstrad MegaPC has. When active it replaces
the stock BIOS routines and allows for easy large HDD usage.
For the 386sx MegaPC motherboard please configure the system BIOS like this:


(click on pic for full size version)

For the 486slc MegaPC motherboard please configure the system BIOS like this:


(click on pics for full size version)

You *need* to have a HDD declared in the BIOS else the system will not succesfuly boot.
It does not matter what the HDD type is, you can use TYPE 1 like on the example or do a HDD Auto-detect
and have whatever User Type the BIOS detects, all it matters is that some type of HDD is declared.
Do not worry about the drive parameters, XT-IDE will take over and things will just work.

When XT-IDE BIOS is activated it will look like this on boot:


(click on pic for full size version)

No further configuration is needed, things will work as normal and you will use the partion/format tools you already use
(either the DOS ones or 3rd party). Be advised that any "HDD OVERLAY" software like DiskManager or EZ-DISK can
interfere with XT-IDE in some configurations. It is recommended to remove such overlays and do a clean install with XT-IDE.

In case you find that XT-IDE BIOS conflicts with your existing setup then you can just physically remove the chip from it's
socket - this will disable the boot rom functionality until the chip is re-inserted and there is no need to change any configurtion
settings on the eeprom or jumpers.


Re-enabling OPL3 when the ALS100 drivers disable it:

Re-enabling the MegaCard OPL3 functionality is only a matter of editing one or two INI files.
The ALS100 driver will disable the OPL3 in software in the following cases:
a. Windows 3x driver installation - the OPL3 driver will not be activated in SYSTEM.INI
b. DOS driver installation - the OPL3 option will be disabled in ALS.INI
c. each time the DOS setup utility ALCONFIG is used - it will disable the OPL3 option in ALS.INI

So the solution to this problem is this:

If you did a DOS installation: then your ALS.INI file is located by default in the C:\ALSOUND directory
(or the directory you chose during installation). Edit said ALS.INI and change the line that reads:
ADLIB=Disabled to ADLIB=Enabled
If successful after a reboot you will have OPL3 enabled in DOS without any warnings or issues.

If you did a windows installation: you must perform the same ADLIB=Enabled change to your ALS.INI
file but this time it will be located in your windows directory (default is C:\WINDOWS)
This will take care of the DOS portion of things but you will need to add some lines to the SYSTEM.INI
file in your windows directory (default is C:\WINDOWS\SYSTEM.INI)

In [386enh] section add this line:
DEVICE=ALOPL.386

In [drivers] section add this line:
MIDI=ALOPL.DRV

If successful after a reboot you will have OPL3 enabled in both DOS and windows environments
without any warnings or issues.


ALS100 general notes:

Please keep in mind that this is a 3rd party SoundBlaster/PRO/16 compatible chip and as such it is not perfect.
So it is natural that some things might not always work good in SB16 mode and you will need to
revert back to SBPRO or plain SB modes... that is not the fault of the MegaCard - it's just the way
the ALS100 is... You might wonder why not another chip was used: basically the ALS100 was available
and it ticked more boxes than the other options, such as correct SB-ADPCM decoding, internal OPL3 DAC,
SB16 compatibility, bug-free MPU401 port, correct L/R mixer channels and general decent performance.
Plus the Avance Logic driver is not bad at all and you can use Unisound as an alternative.

On the Amstrad 386sx motherboard you need to disable the LPT port in the BIOS if you plan to
assign IRQ7 to the ALS100 sound controller.

Some times compatibility depends on the host system: I have found that the 386sx motherboard although
slower is actually more compatible than the replacement 486SLC33 Amstrad motherboard. There are many
factors for this: from the motherboard chipset to the fact that 486SLC is not exactly your bog standard CPU.

I have also found that using IRQ5 for ALS100 is preferable on the 486SLC33 motherboard. If you notice
strangeness using IRQ7 then do a quick switch to 5 and try again - most of the times it will help.
Games like Day of the Tentacle Talkie edition, Indiana Jones and the Fate of Atlantis talkie edition, Monkey Island
Ultimate Talkie (notice the pattern? it's all LUCAS games) , Dreamweb and Mystic Towers all work way better
with IRQ5 on the 486SLC33 motherboard. So keep that in mind :)




The MegaCard addons:

1. The Dreamblaster X3GS wavetable board:

The Dreamblaster X3GS wavetable board is basically the Serdaco X2GS wavetable board built on a different green PCB.
For all intents and purposes the software and hardware features of both are the same. Everything on the serdhashop
page applies to the X3GS as well. This is a very limited one-time run of boards made to match the MegaCard.

Here is how to properly mount the X3GS on the MegaCard:

(click on pic for full size version)

Please make sure you connect the X3GS correctly and both pin rows are inserted and properly aligned
on the MegaCard header , else you risk damage to one or both cards.

Here are some example of how to mount some other Serdaco wavetable boards on the MegaCard


(click on pic for full size version)


2. The MPC010 PCMIDI addon



The MPC010 addon daughterboard is a PCMIDI MPU interface specifically designed to connect to the ISA header of the
MegaCard. When the MPC010 daughterboard is installed you will have a hardware level "Roland Inteligent Mode" compatible
MPU-401 interface available, so any games that require it will run without issues or extra drivers/emulators/workarounds loaded.
You can read more about the PCMIDI MPU on it's website: http://pcmidi.eu/pcmidi.html

The MPC010 will also allow for the 2nd MIDI jack on MegaCard to be configured as an IN port - for music creation reasons :)

When you install the MPC010 the ALS/EXP jumper block on the MegaCard becomes relevant: it allows you to select
which MPU interface (the UART ALS100 one or the Intelligent Mode PCMIDI one) controls which port.
So you can have for example the Wavetable Header controlled by ALS100 MPU at port 300 and Jacks #1 and #2
controlled by MPC010 PCMIDI at port 330 - effectively running a dual-mpu setup.
You can mix and match according to your needs.

To install the MPC010 daughterboard just align it to the headers of the MegaCard and press down gently, that's it!
...and don't forget to set the ALS/EXP jumper block.



These are the jumper settings for the MPC010 daughterboard - you don't really need to change the default IRQ2/port330
resources at all - they are the most game compatible settings and work with both 386sx and 486slc Amstrad motherboards.





...and now some advice you should really consider if you own a MegaPC

My recommendation is to replace the old and limiting stock mechanical HDD that came with the system with a CF or SD card. I can understand some people might not like this - on a normal system I would say it makes no difference if you have a good HDD to use *but* in the crammed MegaPC the power and heat consumption gains are too great to argue against. The system will just run cooler (something that is REALLY needed as Amstrad did not add air intake holes on the MegaPC chassis , this is why the MegaCard bracket is so small as an attempt to compensate for that) and the 65W PSU will have lower load when working: both of these things will be beneficial in the long run for an almost 30 years old system.

MegaCard downloads

ALS100 sound DOS driver only
ALS100 sound DOS - Win3.1x - Win95 driver pack
Realtek 8019 DOS packet driver and configuration utility
Realtek 8019 Windows 3.11 driver
Dreamblaster X3GS downloads
MPC010 PCMIDI downloads

XT-IDE Universal BIOS updates
R620 (2021-10-05)
R622 (2021-12-16)
R622 (2021-12-16) & Y2K BIOS EXTENSION FIX (photo)

Is your MegaCard 3D-printed bracket damaged or you don't like it and feel you can do better? Feel free to download the STL and Solidworks CAD files so you can re-print or improve! If you do improve it, tell me about it :)

Unisound by JazeFox also supports the ALS100 sound chip if you don't want to use the official drivers
mTCP by Michael B. Brutman is the best set of tools for DOS networking , give it a try!




Amstrad MegaPC downloads

These downloads are provided to help MegaPC owners to restore their system's software to a somewhat original state.
Belowe you will find the system's VGA drivers & utilites, the Amstrad Counterpoint frontend and the iconic Amstrad Desktop
that came pre-installed with every MegaPC. For obvious reasons downloads for MS-DOS 5.0 and Windows 3x cannot be provided.

	PC7386SX SVGA Utilities and Drivers (disk images from original media)
	Amstrad Counterpoint v2.5 (disk image from original media)
	Amstrad Desktop MegaPC (unzip to C: drive root using -d switch to restore directories and run with ADT.BAT)
	Amstrad Diagnostics Disk for PC6486SX, PC7286, PC7386SX Official Amstrad Diagnostics Tools used to verify proper operation of systems under service. Disk image provided by DK Shadow , a true rarity!

How to order
You can order a MegaCard by filling the form HERE all sold as of Jan 2022

price for each MegaCard shipped via registered airmail is 210eur
price for the optional X3GS MIDI wavetable daughterboard is 60eur
(can only be bought with a MegaCard)
price for the optional MPC010 PCMIDI expansion is 70eur
(can only be bought with a MegaCard)

Each card comes complete and ready to use with all needed cables and bracket.

Please note that due to lack of time everything is assembled on demand after payment is made.
Because of the amount of time that assembly and testing require allow up to 10 working days before posting.
Packages are sent via registered airmail service provided by Greek Postal Service.
Expedited options are available on demand and extra cost.

Cards are made with high quality components, from the Nichicon MUSE audio capacitors
to the simplest resistor that is 0.5% tolerance or better.



23 Jan 2022 news: All MegaCards sold atm, thanks everyone for your support!

Currently the FPGA needed for the scandoubler functions is out of stock and is affected by the chips
shortage. When the needed FPGA becomes available again in the future more cards can be made.

Contact info

keropi at VOGONS forum




Thanks for visiting!!!

Back to Index

Please check out our other retropc projects: PCMIDI , Orpheus soundcard and Action Rewind

last update: 07-11-2021 , always a WIP