ACA - the Amiga Classic Accelerator.
This accelerator comes with a 50MHz 68030 processor (incl. MMU) in gold/ceramic and 128MBytes physical memory. 1MByte of this memory is reserved for Kickstart re-mapping. This card uses an improved version of our SD-RAM controller that was developed for the previous 55.55MHz accelerator, providing a tiny bit more speed than the sold-out ACA1233-55. Further, Chip RAM access speed has been optimized to the max, giving the user the possibility to squeeze out the last cycle by adapting the access speed to the clock frequency of their main board. Every single card has been tested to be compatible with the rate of overclocking. You may need to remove the cover of your A1200 trapdoor in order to have enough cooling for the processor.
Please note that only the processor of this card is overclocked, while all other components are operated within specification.
The ACA1233n comes with a number of improvements over the predecessor ACA1233. Although clocked at the same speed, performance has been improved in almost every aspect.
The ACA1233n-55 features our IDE speeder technology that accelerates the internal IDE port. Other than competing products, this IDE speeder does 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 and reaches a raw data transfer rate of 11.3 MBytes per second, which results in every-day performance of 5.5MBytes/s with fast CF cards. Fast harddrives with cache may exceed 10MBytes/s performance: The Sysinfo screenshot is taken from a system using a 1998-vintage IBM DTTA 16GB harddisk, connected with a very short cable on a buffered IDE interface. The IDE speeder feature is not available if connected to an ACA500 or ACA500plus.
The ACA1233n-55 boards have much faster memory performance than any other accelerator before - especially with cache and burst enabled. That's because the burst sequence is the fastest-possible sequence that the 68030 can perform: 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. The result is that the ACA1233n-55 is one of the fastest 68030-based accelerators that have ever been sold.
In addition to that, the ACA1233-55 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 ACA1233n cards give a good compatibility boost only because of this little chunk of memory in the right place.
The ACA1233 is PCMCIA-friendly: It will not disable the PCMCIA slot, so you can continue to use a networking card in that slot.
- Memory auto-configuration
- Dynamic clocking for power-saving
- card enable/disable in software
- memory available to onboard CPU if accelerator is switched off
- faster clockport for RapidRoad gives 55% speed increase
- new software compatibility settings
- improved A1200 compatibility
Memory of the ACA1233n is auto-configuring. This means that all memory is available from a power-up without installing any software on the computer. The old ACAtune tool, which was required for our previous accelerators, is not required any more.
If you do not require full speed, the card can be slowed down in order to save power. The CPU governor program will monitor CPU requirement and adapt to the demands of your application, resulting in the best power/performance ratio for your use case.
Some software does not like accelerated execution. For these cases, the ACA1233n can be switched off in two steps: The first step is to switch off the 68030 CPU and give control to the CPU of the host computer. On an A1200, you can still use up to 9MBytes of fast memory, which are also auto-configuring. The second step is to reduce additional memory as well (8M, 5M, 4M, 1M and 0M settings available), getting the computer down to it's stock state without having to remove the card. If used on an ACA500 or ACA500plus, memory can NOT be used by the 68ec000 processor.
The clockport of the ACA1233n can either take an RTC module, or the RapidRoad USB host controller. Operation of RapidRoad is 55% faster than with the internal clock port of the A1200 computer. This function is available in all modes of operation on an A1200 computer, and on the ACA500plus. It is not available if the ACA1233n is operated on an ACA500.
If software is not compatible with 32-bit memory, Z3 autoconfig or newer Kickstart version, the ACA1233n allows downgrading to Z2 autoconfig, older Kickstart versions and also lets you switch off the so-called "trapdoor memory area". The MapROM function is even available on an A1200 if the 68030 CPU is switched off! This will let you use different Kickstart ROM versions without opening the computer and exchanging ROM chips.
Last not least, the ACA1233n features a new A1200 motherboard interface. Some A1200 main boards have been delivered with the wrong timing components and require modification for reliable use with accelerators. With the new improved interface, the ACA1233n is less likely to require these board patches. Although this has been tested extensively, timing patches may still be required.
- Accelerator with RAM and CPU assembled
- short installation manual
You will need in addition to that:
- transfer method for the configuration tool to your Amiga (free download from our wiki)
- motherboard patches as described by Commodore: A1200 capacitors E123C and E125C may need to be removed.
Processors on this card are used and may have scratches. Jumper wires for implementing added stability and IDE speeder technology are not shown in the picture.