Search found 2335 matches

by TmEE co.(TM)
Wed Apr 24, 2019 3:31 am
Forum: Demos
Topic: MD-NICCC - a 3D Mega Drive experience by TiTAN
Replies: 8
Views: 210

Re: MD-NICCC - a 3D Mega Drive experience by TiTAN

I cannot understand how SNES version that uses SuperFX still runs muuuuuuuch slower....
by TmEE co.(TM)
Wed Apr 24, 2019 3:29 am
Forum: Super 32X
Topic: Using 32x as a 3rd plane, possible?
Replies: 5
Views: 267

Re: Using 32x as a 3rd plane, possible?

When 32X is enabled the ROM is only in $880000 to $9FFFFF, the first 4MB no longer has ROM in it. See page 15 for more info : http://www.tmeeco.eu/SMD/32x_hardware_manual.pdf
by TmEE co.(TM)
Sat Apr 20, 2019 1:53 pm
Forum: Video Display Processor
Topic: Help scale and rotation sega genesis
Replies: 33
Views: 2053

Re: Help scale and rotation sega genesis

I don't actually know if there's one or few ideal moments in the sync period to do the switch since I haven't actually experimented with it. There will not be a moment that will produce exact line length so you will only get to choose between very off and little bit off. Real world tests are needed ...
by TmEE co.(TM)
Fri Apr 19, 2019 8:22 pm
Forum: Video Display Processor
Topic: Help scale and rotation sega genesis
Replies: 33
Views: 2053

Re: Help scale and rotation sega genesis

Even then, a line is still a line regardless of where it is in the frame. There's 262 lines in 60Hz and 313 lines in 50Hz, rest are border, blanking and sync. Lines themselves all consist of border, active part, blanking and sync aswell, and switch can happen in the sync portion. Composition of one ...
by TmEE co.(TM)
Fri Apr 19, 2019 7:45 pm
Forum: Video Display Processor
Topic: Help scale and rotation sega genesis
Replies: 33
Views: 2053

Re: Help scale and rotation sega genesis

Switch must happen not just in horizontal blank, it must be in horizontal sync position of the line. You do your switch at any line you desire during the frame, but the switch itself must happen in sync portion of the line you do it on.
by TmEE co.(TM)
Thu Apr 18, 2019 10:28 am
Forum: Video Display Processor
Topic: Help scale and rotation sega genesis
Replies: 33
Views: 2053

Re: Help scale and rotation sega genesis

Enabling/disabling display isn't gonna do anything with that, video line generation is an autonomous process that runs always and depends on if internal dot clock or EDCLK is used (bit7 or VDP register $07). in H256 (256 pixels + internal dot clock) all pixels are 10 MCLKs long, while in H320 (320 p...
by TmEE co.(TM)
Wed Apr 17, 2019 11:00 pm
Forum: Video Display Processor
Topic: Help scale and rotation sega genesis
Replies: 33
Views: 2053

Re: Help scale and rotation sega genesis

This has been done and it doesn't work really well since the line where the switch happens will have different timings from the rest and that does upset some TVs etc. by making them do weird noises or other oddities. You can reduce the problem by doing the switch during horizontal sync pulse but the...
by TmEE co.(TM)
Sat Apr 13, 2019 9:01 pm
Forum: Video Display Processor
Topic: Is this just shadow effect?
Replies: 1
Views: 128

Re: Is this just shadow effect?

Yes, it is done with Shadow function.
by TmEE co.(TM)
Sat Apr 13, 2019 12:07 am
Forum: Super 32X
Topic: Using 32x as a 3rd plane, possible?
Replies: 5
Views: 267

Re: Using 32x as a 3rd plane, possible?

Soleil does checkerboard pattern which you could do on the 32X too, but you're not gonna get any real shadow/highlight type stuff without recreating the MD image on 32X side.
by TmEE co.(TM)
Fri Apr 12, 2019 6:54 pm
Forum: Super 32X
Topic: Using 32x as a 3rd plane, possible?
Replies: 5
Views: 267

Re: Using 32x as a 3rd plane, possible?

32X output can only be above or below MD layer, it cannot do intermediates. Only way you could do some shadowing etc. is to render the output of MD itself on 32X side and apply whatever you want. As far as other stuff goes, no, you cannot really do that. 32X changes the memory map drastically, at be...
by TmEE co.(TM)
Fri Apr 05, 2019 7:28 pm
Forum: Cartridge
Topic: EEPROM mapping for homebrew
Replies: 9
Views: 488

Re: EEPROM mapping for homebrew

Yeah, that would work better, no bus fights possibility at all ~
by TmEE co.(TM)
Wed Apr 03, 2019 10:14 pm
Forum: Cartridge
Topic: EEPROM mapping for homebrew
Replies: 9
Views: 488

Re: EEPROM mapping for homebrew

I would use an SPI or µWire EEPROM instead rather than I2C types, they're much easier to talk to (thus less hardware). Here's something I devised a while ago :
Image
by TmEE co.(TM)
Sat Dec 22, 2018 1:00 pm
Forum: SGDK
Topic: VDP_loadTileData CPU vs DMA differences?
Replies: 5
Views: 693

Re: VDP_loadTileData CPU vs DMA differences?

DMA doesn't cross 128KByte boundaries but wraps around within 128KB block.
by TmEE co.(TM)
Fri Nov 23, 2018 4:06 am
Forum: Sound
Topic: New Documentation: An authoritative reference on the YM2612
Replies: 859
Views: 345126

Re: New Documentation: An authoritative reference on the YM2612

It is possible to update DAC once every sample if you have cycle synchronity to the YM. I did some tests where YM and Z80 were made to share the clock in MD and I could get unique samples out every 144 cycles. Doing rates between full and half sample rate are very ugly though due to the "resampling"...
by TmEE co.(TM)
Sat Nov 17, 2018 9:59 pm
Forum: Hardware
Topic: Controllers and wrong I/O pin directions
Replies: 9
Views: 1854

Re: Controllers and wrong I/O pin directions

That resistor is the same as 330ohm to ground if it connects to another output, kind of like both outputs driving to a 330ohm load if their states differ (one side high, other low and vice versa). It is a current limit and roughly like lighting up a LED via an IO pin. I'm sure the IO port output dri...