Commodore A1200 Reloaded

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Much like the C64 Reloaded, the Commodore A1200 Reloaded will be a new motherboard using original MOS/CSG chips. It does not directly compare to any existing Commodore Axxx mainboard, but if you want a comparison basis, then an A1200 is probably the closest match. However, there are differences that also make it very much "not A1200".


current status, time frame, target price

The following is a preliminary specification. Things may change, as there's a lot of work to do. The current plan is to build the first prototype in 2017. After development is done, we will start taking pre-orders, so we can find out the initial demand. This will be different from the proceedings of the C64 Reloaded: With a sufficient quantity of AGA chips in our stock, there is a technical limit, but we don't expect it to be an actual limit. The target price of the main board with AGA chips, DVI-I output and RTG solution is in the 350,- EUR ballpark

Form factor

Commodore's "multimedia wonder machine" became really popular when the A500 has hit the market: A computer in a keyboard case. We therefore mainly aim at the A500 case. A second target will be the A1200 case: We'll do everything that's possible to make one single design fit both these very popular cases. We've already heard calls to make it fit the A600 case as well, but that's currently on the "nice to have" list, and not a "must have". There is one prime directive for the form factor design: The target cases are classic computer cases, so "little to no" modifications shall be required to install the board.


Commodore A1200 Reloaded is an AGA-based computer using the original chips Alice, Lisa and Paula, along with two CIA chips. Other chips of the computer will be replaced by modern logic chips. Chipram is one of the special things where the Commodore A1200 Reloaded scores: Although it's "only" 2MByte Chipram like all other AGA machines before, the memory is much faster and can be accessed by the processor at full speed even when eight bitplanes are switched on. This is accomplished by making use of modern memory technology, which is a lot faster than the D-RAMs that the AGA chipset was designed for. The higher speed allows inserting extra timeslots between the original DMA slots of the Alice chip.

As a result, the CPU will have high-speed access to chip memory even when 8 bitplanes are used, or the blitter is in "nasty mode", where it will not slow down if the processor signals that it wants to access chip ram. However, this may cause undesired effects with software that can't handle this kind of speed, so this feature can be switched off at the user's choice while the machine is running (no reboot required). It may also be a good idea to patch system functions to not use the blitter, but the CPU to do blitter functions, because the CPU will outperform the blitter in many, if not all aspects, given that it will have at least 14MByte/second performance on chipram. We currently have no plans to provide such a software patch, but encourage authors to continue the work that can be found on Aminet: None of the existing "CPU blit" programs really patch all system functions that use the blitter.


The Commodore A1200 Reloaded will not have any CPU. We know that there are many flavours of Commodore fans out there, and each of them defines "favourite computer" with their own standards. While some of you will primarily use less CPU-demanding programs, others want the highest possible performance. This means that no matter what type of CPU we would choose, it would be the wrong choice for many customers. We therefore let the customer make the decision: The Commodore A1200 Reloaded has an A1200-compatible CPU slot where a CPU card must be installed to operate the board. Compatibility of A1200 accelerator boards will be the same as with the ACA500(plus): We will guarantee that our ACA12xx cards work (except for the old ACA1230 type), and we'll also do our best to make the popular Blizzard cards work. However, there will be no product support for operation with non-iComp branded CPU cards.

The choice of no CPU on the mainboard has two main advantages: For one, you don't have to pay for a CPU that you don't use anyway. Second, it gives you the possibility to build a very low-cost computer with the ACA1221(EC) cards.

Power supply

The Commodore A1200 Reloaded will use a modern laptop power supply as it's only power source. Input voltage may range from 14V to 19V DC. Modern DC-DC voltage regulators will provide proper regulation of all local voltages with enough power reserves for top-notch expansions. At the same time, the choice of local DC-DC conversion eliminates cross-regulation trouble that most PC power supplies are exhibiting these days.

Even with today's standards, an AGA-based computer can be considered a low-power system. The Commodore A1200 Reloaded will add to this property with it's very high-efficiency switching regulators.


The Commodore A1200 Reloaded has a DVI-I output as standard. This will allow you to use any modern monitor, and even flat-screen TVs with HDMI output (adapter cable required). The Flicker fixer functionality is the same as our very popular product "Indivision AGA MK2", but there's more: This version of Indivision AGA MK2 includes a graphics card that can be used with the P96 RTG software.


The old RCA connectors won't be there. Instead, the Commodore A1200 Reloaded will use a 3.5mm stereo jack just like today's PCs. There are a lot of audio peripherals available that use this kind of connector.


A jumper will select if you want to use an A500 or an A1200 keyboard. Although LEDs may get in the way (and might need modification), this will let you use an A1200 keyboard in an A500 case and vice versa. This will give you the opportunity to create your unique colour combination. Following the idea of not requiring any case modification(s), the keyboard will also be used to switch the computer on/off.


The Kickstart ROMs will be properly licensed, and will be stored in a flash ROM. Flash space will be 8MByte.

Floppy Disk

We all love and hate them. Real 880k-disk drives are hard to come by, and they are even harder to repair. The Commodore A1200 Reloaded will therefore have a floppy drive connector that's compatible with PC disk drives, so a cheap replacement disk drive from any outdated PC can be used. This drive will work like an original 880k disk drive without electrical modifications. All track loaders and copy-protected games will work. If you happen to have a working original disk drive, this may be a better choice due to the eject button and metal cover. The 34-pin floppy connector can be made compatible to the original disk drives (or drive emulators) by changing a jumper block. There will be no DB23 disk drive expansion port.

Parallel/Serial/Mouse/Joystick ports

These ports are identical to the ones used on the A500 and A1200. The Parallel port was used a lot for sound samplers, printers and ParNet, whereas the Serial port was used for MIDI and Nullmodem purpooses. Using the original DB25 connectors ensures that this existing hardware will work out-of-the-box. The same applies to Mouse and joystick ports, which will use the original DB9 connectors.

IO Subsystem

The Commodore A1200 Reloaded will use a 32-bit IO subsystem for mass-storage and IO expansion. The standard performance of this subsystem is 14MB/s raw data, which is about the performance that you also get from Z3 and popular IDE speeders. We may be able to exceed this performance with certain accelerators.

Mass Storage

Two CF-card slots will give the Commodore A1200 Reloaded the same capabilities like the ACA500 and ACA500plus. The Boot card will be internal, and the aux card will be accessible from the outside of the computer: Either through the PCMCIA slot of an A1200 case, or through the DMA slot of the A500 case. Note that the CF cards are part of the 32-bit IO subsystem, so they are considerably faster than the IDE of an A1200 computer.

USB expansion

USB functionality can be added with the X-Surf-100 version of RapidRoad. This is the lowest-cost version of the product, yet the one with the highest-performing interface. Since this connector is part of the 32-bit IO subsystem, it will meet or exceed Z3 speed.

Network expansion

The Commodore A1200 Reloaded will use the same expansion port as the ACA500 and ACA500plus for a networking card. This will give you 100MBit Ethernet at a considerably lower price than the X-Surf-100, yet with the same kind of performance of the product.

further expansion

With the A1200, Commodore has introduced a pin header that was later on called the "clock port". Individual Computers was among the first (if not the first) to make use of this port, which is why we've added this pin header to many of our expansions (including expansions for the C64). The same is true for the Commodore A1200 Reloaded: At least two clock ports will be on the board, which can be used to add an RTC module or other clockport expansions. The speed of the clock ports will be configurable either to original speed (for highest compatibility) or to higher speed as seen on our Zorro cards.


After we've finished the first prototype, we will take binding orders to find out the actual demand of the Commodore A1200 Reloaded. After this order phase is over, production will start and the boards will be delivered about 18-20 weeks after the initial order phase. It will be for the first time that we are taking money from customers before mass-production has started. Should you not trust us, we recommend to pay with PayPal: One of the changes they have done lately to their terms is that buyer protection can be requested for up to 180 days after the payment. Should there be any delay that lets you lose trust in the project, you can safely ask your money back - not just guaranteed by iComp, but also guaranteed by PayPal, who are known to be very customer-friendly. On the legal side, we will not treat your order as "built to your specification", which would be a backdoor for cutting down on your right of revocation. We'd like to emphasize that your right of revocation remains in place until 14 days after the product has arrived at your place.

Since we have considerably more AGA chipsets than C64 chipsets in stock, it's unlikely that there will be a shortage. We're open to positive surprises, though!

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