ACA1234-25 128 MB accelerator

ACA - the Amiga Classic Accelerator.

The ACA1234-25 128 MB is a medium-class accelerator. 25MHz version: >5700 Sysinfo-Dhrystones, about 5.9MB/s local CF performance

Technical data

• CPU 68030 (incl. MMU), 25 Mhz to 26,67 Mhz overclocked
• 128 MB Ram
• MapROM
• PCMCIA-friendly
• Local CF card slot
• Faster clockport (Fastclockport)

The ACA1234 replaces all previous accelerators that we have offered with 68030 processor. While it maintains most technical data of the predecessors, it adds high-speed mass storage, improving the overall speed experience of your computer even more than the IDE speeder does, which is also available on this model. With 8MBytes of local flash memory and a local CF card slot, the ACA1234 is ideal for anyone who wants to get back into the Amiga hobby, but is not comfortable opening the computer for adding mass storage.

While our IDE speeder technology accelerates the internal IDE port to raw transfer rates of up to 14MBytes/s (resulting in every-day performance of around 5MBytes/s with CF cards, or up to 9MB/s with physical harddrives), the local CF card slot can exceed 9MBytes/s. Other than competing products, both options do not require opening the computer or even removing chips from their socket. The IDE speedup to PIO mode 4 is activated with a software setting. The IDE speeder feature is not available if connected to an ACA500plus.

The ACA1234 boards take memory performance to the limit of what a 68030 processor can transfer in a burst sequence: It's a sequence of four 32-bit transfers in four CPU cycles, which has not been shown before we first introduced the ACA1230 in 2010. You therefore get the best performance per MHz compared to both DIY products and legacy 68030 designs. In addition to that, the ACA1234 makes sure that the exec base in burst-capable, cacheable 32-bit fastmem. This is another "first" that we've introduced to the world of 68020/68030 accelerators for the A1200.

Another huge improvement over older accelerators is memory mapping to the legacy 0x00c0.0000 address. This is the location where many A500 games expect a trapdoor memory expansion. The ACA1234 cards give a good compatibility boost only because of this little chunk of memory in the right place.

The ACA1234 is PCMCIA-friendly: It will not disable the PCMCIA slot, so you can continue to use a networking card or a CF card adapter in that slot. For the easiest-possible transfer of files, drivers for a PCMCIA-CF card reader are included in the flash of this accelerator. You can access PC-formatted and Amiga-formatted cards. If desired, you can even boot from a CF card in the PCMCIA slot. This is possible without any further software installation, breaking the chicken-and-egg circle of the "first transfer": For most other file transfer methods, you need to transfer drivers to the system.

Customers who are returning to the "hobby Amiga" often have the problem of lost installation disks, or even a defective floppy drive after all these years. Installing a system becomes almost impossible in such cases. The ACA1234 includes all means to install a system in such a case as well: Both ROM and install disks are licensed from Hyperion and included in the flash of the ACA1234. Our installer, which has been successfully used with the ACA500plus and Buddha as well, installs a system way faster than it will ever be possible with floppy drives - and it only take a few mouse clicks. This includes automatic partitioning of media that's larger than 4GBytes.

All features

1. 127 MByte RAM auto-configuration
2. 1 MByte RAM reserved for fast Kickstart re-mapping
3. 8 MByte flash for installation files and Kickstart ROMs
4. Local CF card slot as high-speed mass storage
5. IDE speeder technology for read and write
6. drivers for PCMCIA-CF card reader in flash
7. ROM and OS3.1 in flash, extremely fast system installation
8. clock rate can be reduced (reset required)
9. card enable/disable in software without power-cycling
10. faster clockport gives 55% speed increase
11. field-proven high A1200 compatibility

Memory of the ACA1234 is auto-configuring. This means that all memory is available from a power-up without installing any software on the computer.

If you do not require full speed, the card can be slowed down in order to save power or reduce heat. You can also increase the speed beyond rated clock rate for a trial period - if you find that your CPU can accept a certain level of overclocking, you can purchase a permanent overclocking license. This also provides an upgrade path for users who have exchanged the CPU with a faster speed grade. Available speeds on the ACA1234 are 25MHz, 33MHz, 40MHz and 50MHz. Changing the clock speed always requires re-booting the computer.

Some software does not like accelerated execution. For these cases, the ACA1234 can be switched off and put into a "stealth mode": This will allow you to run such software without having to remove the accelerator. Returning to 68030 operation does not require the computer to be power-cycled.

The clockport of the ACA1234 can either take an RTC module, or a different clock port device. Operation of such a clock port device is 55% faster than with the internal clock port of the A1200 computer, provided the drivers support the address of this port. This function is available in all modes of operation on an A1200 computer, and on select ACA500plus models with updated CPLD.

Last not least, the ACA1234 features our field-proven A1200 motherboard interface. Some A1200 main boards have been delivered with the wrong timing components and require modification for reliable use with accelerators. With our interface, the ACA1234 is less likely to require these board patches. Although the ACA1234 will work reliably with any patch level of the A1200 main board, you may still want to perform these patches, as they also fix graphics glitches with Super-Hires resolutions of the AGA chipset.

Package contains:

• Accelerator with RAM and CPU assembled
• short installation manual

You will need in addition to that:

• motherboard patches as described by Commodore: A1200 capacitors E123C and E125C may need to be removed.
• a proper power supply that provides good regulation, even when loaded with expansions (see icomps PSU FAQ)
• if desired, a PCMCIA-CF card reader

Processors on this card are used and have scratches.