potatohead's Blog

That is impressive! I presume that using a real 6502 may be a way of getting around propeller memory constraints?

 

Barnie

Well, some of them.

 

I thought about bagging on my 6502 + Prop project, but have decided to get it built and running anyway.

 

Propeller has 32K of shared memory among it's 8 processors. Each processor has 2K of memory where it's assembly code runs.

 

Ideally, a real 6502 would free some shared memory, and a processor or two, for doing other things.

 

At the end of the day though, 32K isn't as much as people would like. That means paging, via SD card, external serial RAM, or full on running another Propeller, or RAM chips.

Darryl's effort is most impressive, especially given the number of bugs I left him with.

 

Just to elaborate on Propeller RAM - each 32bit processing core has 2K (496x32bit) of private RAM for code and local data/registers. There is 32K of on chip shared RAM used for shared data and SPIN bytecode. Access to the shared RAM is slower 4-8 times slower than private RAM. The Propeller does not have an external memory bus architecture - only 32 GPIO pins. An external memory can be attached, but it cannot be used to store code directly. The RAMBlade is a design with a 512Kx8 SRAM connected directly to the Propeller.

Yes it is!! Most of us are stunned.

 

Thanks for the clarification. I never know how much detail to return to that particular query.