The SymbOS operating system runs fine on Isetta. But when you have several programs open, and use a few of it's advanced options, the 384kByte available memory on a 512kB system is in many cases not enough.

Therefore, I added another 512 kByte RAM to Isetta. The bankswitching system got an extra chip to handle the extra address bit, and a quick pcb redesign was done. The pcb was built, and a low-level memory test proved that the extra RAM  was working.

Work to let SymbOS use the extra RAM is still in progress, and hopefully can be finished soon.

If you order a kit, you will get the 1024 kByte version from now on.