30-01-2026, 12:04 PM
Hey Matty.
In hindsight, well after the release of the Premium Plus, I wished I had not released uClinux for it.
It was a difficult implementation for a number of reasons, most particularly the keyboard and the shared memory access portion of the uCLinux available address space being very slow.
While the Coldfire processor ran quite well with it's internal ram (64k) the external bus interface only had 2 chip selects and both were for 8 bit accesses. One of the chip selects could run
at the speed limit of the ram (55ns) while the other was shared between the FPGA interface to the screen and I/O area of the Z80 buss and the other 1Mb ram. This meant that the timing
for that chip select had to cater for the slowest devices attached to it - 300ns cycles for the Video section. There were some work-arounds that I implemented, but generally I consider it as
'It runs, and that's impressive, but I shouldn't have gone down that path'.
There is no plan at this stage to release uClinux on the new machines, even though they have a 66Mhz 68k processor. There is also no ethernet on the new machines.
Looking at other OS alternatives for the 68K side of things for the new machines.
In hindsight, well after the release of the Premium Plus, I wished I had not released uClinux for it.
It was a difficult implementation for a number of reasons, most particularly the keyboard and the shared memory access portion of the uCLinux available address space being very slow.
While the Coldfire processor ran quite well with it's internal ram (64k) the external bus interface only had 2 chip selects and both were for 8 bit accesses. One of the chip selects could run
at the speed limit of the ram (55ns) while the other was shared between the FPGA interface to the screen and I/O area of the Z80 buss and the other 1Mb ram. This meant that the timing
for that chip select had to cater for the slowest devices attached to it - 300ns cycles for the Video section. There were some work-arounds that I implemented, but generally I consider it as
'It runs, and that's impressive, but I shouldn't have gone down that path'.
There is no plan at this stage to release uClinux on the new machines, even though they have a 66Mhz 68k processor. There is also no ethernet on the new machines.
Looking at other OS alternatives for the 68K side of things for the new machines.