Subversion Repositories 6809_6309_compatible_core

Changelong

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31.12.13

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- Implemented TFR/EXG

- MC6809_cpu.v: Added one more state to execute TFR or EXG

- decoders.v: added source/dest for TFR and EXG

- regblock.v : added second write path to the registers for TFR&EXG

- defs.v defined new SEQ_TFREXG for tfr&exg execution

30.12.13

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- Fixed increment/decrement of the stack pointer

- MC6809_cpu.v: Push/pull increment/decrement the stack pointr in their own states

                Added eamem source to the left alu data path to check for zero in the ea (leax/leay)

29.12.13

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- Fixed wrong byte in SEQ_MEM_WRITE_H

- Fixed unaffected Z flag for LEAX/LEAY

- Moved increment of pc from FETCH_2 to FETCH_1

- Fixed CMPA/CMPB/CMPX, they don't write a register back

- Fixed late write of pc

- decoders.v: Merged separated write_dest_x into one wire

              Added a source_size wire to indicate the width of the source argument

              Added the recognition of LEA as an alu mnemonic to modify the Z flag for LEAX/LEAY

- MC6809_cpu.v: Dropped checks for source size from the individual states and moved

                into SEQ_MEM_READ_H

                Merged write flags into k_dest_write

- alu.v: Added a LEA instruction for LEAX/LEAY where only the Z flag will be affected

- defs.v : added a LEA define to the ALU section