Search found 206 matches

by HardWareMan
Mon Nov 19, 2018 6:48 am
Forum: NES Hardware and Flash Equipment
Topic: Nes Clone MOD
Replies: 8
Views: 9834

Re: Nes Clone MOD

The T1818P is a NoC, used in russian clone Dendy. Unlike UM6561 it has no SRAM inside, so it required external SRAM. But it has full set of pins for controllers and even EXT port. You can trace it using this images of board: Top Bottom Internal 1st joypad in your clone is that little PCB. You should...
by HardWareMan
Sat Apr 21, 2018 12:24 am
Forum: NESemdev
Topic: PAL color palette emulation
Replies: 79
Views: 45631

Re: PAL color palette emulation

Of course here no negative values at RGB output to the tube. Because the last stage with DC path. And at this stage does secondary recover black level right before x-Y signals meets with Y. Before this all paths separated with capacitors, so they have negative signals, like any other amplifiers does...
by HardWareMan
Fri Apr 20, 2018 11:45 pm
Forum: NESemdev
Topic: PAL color palette emulation
Replies: 79
Views: 45631

Re: PAL color palette emulation

None. TVs recover black level from front porch. Where color burst placed. Manipulating with this level was a copy protection at that years. And that's why "darker than black" color a present: Luma0 is lower than black level . On CRT TV you can see that luma level only if add some brightness. Black l...
by HardWareMan
Thu Feb 16, 2017 5:46 am
Forum: Other Retro Dev
Topic: DRAM refresh cycles on Genesis and NES
Replies: 9
Views: 5218

Re: DRAM refresh cycles on Genesis and NES

And true: 32 bit access must be word aligned as 16 bit access, because M68000 has only 16 bit data bus and split 32 bit access into 2 of 16 bit access. For M68000 only 8 bit access can be not aligned by word.
Image
by HardWareMan
Mon Oct 31, 2016 11:19 pm
Forum: NESemdev
Topic: LDA 0x2007 is counterintuitive !?
Replies: 7
Views: 3647

Re: LDA 0x2007 is counterintuitive !?

So, what is the first result of a LDA 2007 (when there is no previous read)? Zero? It depends on whether the PPU initializes that buffer with anything during its power up sequence, buy I don't see why they'd waste resources on something like that. The first $2007 read result will be $00, as documen...
by HardWareMan
Mon Oct 31, 2016 7:00 am
Forum: NES Hardware and Flash Equipment
Topic: Save state format for Everdrive N8
Replies: 1
Views: 1993

Re: Save state format for Everdrive N8

Why do you ask this here?
by HardWareMan
Fri Sep 30, 2016 8:59 pm
Forum: NESemdev
Topic: PAL color palette emulation
Replies: 79
Views: 45631

Re: PAL color palette emulation

Analog TV has no any horizontal "pixels", only vertical by scanline count. There is only high frequency limit, that will describe how smallest object can be shown (video clarity). For 576i it is ~5,5MHz for BW only luma and <4MHz with PAL color encoding. For 480i as far I know it will be ~5MHz for B...
by HardWareMan
Tue Sep 20, 2016 11:26 pm
Forum: NES Hardware and Flash Equipment
Topic: How to check 2A03 fake or original?
Replies: 3
Views: 2014

Re: How to check 2A03 fake or original?

They are all used. Not new. But they all seems working fine.
by HardWareMan
Sun Jul 03, 2016 2:45 am
Forum: NESdev
Topic: New NTSC decoder with integer-only math (short C++ code)
Replies: 30
Views: 26875

Re: New NTSC decoder with integer-only math (short C++ code)

I've got right palette with phase 8 in CPLD generator. Here is verilog: module PAL_NTSC_Gen( input NTSC_Clk, // 21.4772 MHz input PAL_Clk, // 53.2034 MHz output [7:0]DAC, output [3:0]COUT, output [12:1]PHOUT ); // For test purpose assign COUT[3:0] = HCOUNT[7:4]; assign PHOUT[12:1] = PH[12:1]; // Рег...
by HardWareMan
Sun Jul 03, 2016 2:40 am
Forum: NES Hardware and Flash Equipment
Topic: Unequivocal proof that 2C02 colorburst is phase 8
Replies: 11
Views: 7443

Re: Unequivocal proof that 2C02 colorburst is phase 8

2- An AGC, if even active on an S-Video input, will not care about the chroma and luma components relative to each other . That's the entire point of S-Video. There is AGC in RGB matrix and amplifier right before CRT. This is where luma from your S-Video meets with chroma from decoder. Also there h...
by HardWareMan
Sun Jul 03, 2016 12:03 am
Forum: NES Hardware and Flash Equipment
Topic: Unequivocal proof that 2C02 colorburst is phase 8
Replies: 11
Views: 7443

Re: Unequivocal proof that 2C02 colorburst is phase 8

Not unequivocal for me. You violate raster timing and many AGC's in monitor/TV getting mad. For example, black level restorer, that use front porch for it (where color burst placed). Now. Working on BreakNES project, we discovered this level assignment: LEVEL : SYNC : BURST : LUMA0 : LUMA1 : LUMA2 :...
by HardWareMan
Tue Jun 21, 2016 3:46 am
Forum: NESdev
Topic: New NTSC decoder with integer-only math (short C++ code)
Replies: 30
Views: 26875

Re: New NTSC decoder with integer-only math (short C++ code)

I presume you are doing NTSC signal to RGB conversions. The code I pasted generates 32-bit integers where certain eight bits represent blue, certain eight bits represent green, and certain eight bits represent red. (Lowest-order eight bits are red IIRC.) It's up to the user to ensure they map the r...
by HardWareMan
Tue Jun 21, 2016 3:32 am
Forum: NESdev
Topic: New NTSC decoder with integer-only math (short C++ code)
Replies: 30
Views: 26875

Re: New NTSC decoder with integer-only math (short C++ code)

Bisqwit wrote:Make sure your blue and red are not swapped (RGB v.s. BGR).
How can it possible? It's just a 12 square waveforms with linear phase shift.