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pProp040 is a new design in the pPropQL series, based around a MC68(LC)040 and a Parallax Propeller. (While it is not intended to run any QL software per-se nothing impedes it either. A reconfiguration of the memory map may be needed.) This system builds on the experience gained through the other systems but using a even more powerful processor.
A single board computer able to run a variety of OSs. The availability of a MMU means that un*x derivatives could be used.
1. Main Board
MC68040 Processor, intended frequency is 25 to 33 MHz (depending on processor available). Up to 16MB (x32) Static RAM with 2 cycle access (fastest) and 2-1-1-1 burst access (8 MB per board, two boards can be stacked for 16 MB). Parallax Propeller as boot device and slow text video interface (for testing and prototyping). 32 bit Video subsystem. 32 bit Video subsystem shares memory with the processor using BG/BR/BB protocol, synchronous to the processor clock, so 25 MHz and 33 MHz for 640x480 or 800x600.
<span style"font-size: 1.3em;">1.1 Design===
The 5 V MC68040 is interfaced to 5V memory and to a 5V tolerant CPLD. The CPLD runs all the glue logic and decoding needed to map memory and to guaranty fast memory access. The '040 does not have dynamic bus sizer thus a extra FPGA (the video controller) will act as one. Level shifting is only needed for the propeller, connected to the FPGA and the SD cand also connected to the FPGA.
The design show above has been sent for manufacturing and 4 prototypes have been made. Currently waiting for the 040s to arrive. The glue-logic has been partially written (Verilog) and tested.