CPU is running

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:

I’ve assembled a short program looping on STA instruction, put it in 0000 address using monitor, set RESET Vector to 0000 and started 65816 CPU…

0000  8D 34 12                   STA $1234
0003  4C 00 00                   JMP $0000

Picocomputer 65816
RIA Mar 10 2024 14:49:28

]0000 8D 34 12 4C 00 00
]fffc 00 00
]0000
000000 8D 34 12 4C 00 00 66 77 88 99 AA BB CC DD EE FF
]fffc
00FFFC 00 00 00 00
]reset
starting
CPU: 0x00FFFF R
CPU: 0x0001D4 R
CPU: 0x0001D3 R
CPU: 0x0001D2 R
CPU: 0x00FFFC R
CPU: 0x00FFFD R
CPU: 0x000000 R
CPU: 0x000001 R
CPU: 0x000002 R
CPU: 0x001234 w
CPU: 0x000003 R
CPU: 0x000004 R
CPU: 0x000005 R
CPU: 0x000000 R
CPU: 0x000001 R
CPU: 0x000002 R
CPU: 0x001234 w
CPU: 0x000003 R
CPU: 0x000004 R
CPU: 0x000005 R

As you can see the processor did the proper RESET sequence (reading some “random” memory addresses), then Read the RESET Vector (0000) from address FFFC-FFFD, then Read the STA $1234 instruction from addresses 0000-0002, then did a Write to address 1234, next Read JMP $0000 instruction from addresses 0003-0005 and looped back to Reading from 0000. ➿

RIA memory emulation code is done! 🎉