Quote:
Originally Posted by dreampeppers99
As runawayprisoner have said... I've just plus one thing.
I believe that PONG uses the FONT scheme instead of BCD so checks your insctructions to font...
FX29 I points to the 4 x 5 font sprite of hex char in VX
Fx29 - LD F, Vx
Set I = location of sprite for digit Vx.
The value of I is set to the location for the hexadecimal sprite corresponding to the value of Vx. See section 2.4, Display, for more information on the Chip-8 hexadecimal font.
Source
See if you are correct with this too. |
Just correcting something that I think Cowgod is making look confusing.
FX29 should be...
LD I, F[VX]
or...
LDF VX
Instead of...
LD F, VX
Because there is no F register, so if you put F in there in the disassembler along with LD, it looks really confusing. rather... LD I, F[VX] seems cleaner.
Similarly,
FX33 should be...
LD [i], BCD[VX]
or...
LDM I, BCD[VX]
or...
BCD VX
Instead of...
LD B, VX
And again, just because there is no B register.
I know some of us have the habit of making a universal LD function that takes any value from a register and load it into another register... so if you use that convention for F and B, it'll return an error or do something else altogether.
Be careful.
(I realized this error from my Gameboy emu... ack...)
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