PARALLAX P8X32A-D40 IN REPLICA I PLUS QUESTION

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PARALLAX P8X32A-D40 IN REPLICA I PLUS QUESTION

What function does the Parallax P8X32A-D40 Propeller serve in the Replica I Plus (and in the L-Star Plus)?  The schematics don't make that clear.  (At least not to me.)  I want to be able to control an external LED and other simple external devices.  I can't find any info on using the  external expansion connector on either of these Apple I (more or less) replicas other than what the pinouts on the connectors are.  As you can tell, I'm totally inexperienced at using the expansion connectors and a novice at using 6502 assembly language. 

THANKS for any help you can provide.

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The Apple I consists of two

The Apple I consists of two (mostly) separate circuits: a 6502 microcomputer, and a video terminal. So to replicate these functions, you need a CPU (acting as a 6502), memory for the processor, something that acts as a video terminal, and memory for it, plus I/O for the keyboard and anything else. A Propeller chip can be programmed to generate video easily—it is one of the applications in its data sheet. So the Propeller in this system is used for generating the character display on the screen. It can also have other functions simultaneously such as I/O but I am not familiar with these specific details.

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THANKS

Thanks for the explanation.

 

Jim

 

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