Search found 2594 matches

by Chilly Willy
Fri Oct 19, 2018 2:04 am
Forum: SGDK
Topic: Question about VDP_showFPS
Replies: 6
Views: 142

Re: Question about VDP_showFPS

The routines use the current text plane for drawing the fps. Use VDP_setTextPlan() to change the text plane before showing the fps. The coords are fixed in the source. You can alter your local copy of SGDK by changing the line // display FPS VDP_drawText(str, 1, 1); Change the 1, 1 to whatever x/y y...
by Chilly Willy
Fri Oct 19, 2018 1:59 am
Forum: Demos
Topic: Game similar to Resident Evil
Replies: 17
Views: 1939

Re: Game similar to Resident Evil

Appear in the original posts fine here as well.
by Chilly Willy
Thu Oct 11, 2018 2:08 pm
Forum: Sound
Topic: YM2612 clock stopping
Replies: 3
Views: 215

Re: YM2612 clock stopping

Weird, but not unprecedented - the 6502 could be stopped by holding the clock high. That's how the Atari 8-bit computers worked since the RDY line didn't work on read, only write. When the ANTIC needed the bus, it would assert a signal that went to the clocking circuit that caused the 6502 clock to ...
by Chilly Willy
Thu Oct 04, 2018 3:58 pm
Forum: Hardware
Topic: Second Dimension PCB's
Replies: 6
Views: 385

Re: Second Dimension PCB's

Over on discord, we've been talking about a cheap flash cart for small projects. It would use a 1Mx16 or 2Mx16 NOR flash ($1.28 and $2.13 in single units at Digikey), and like five 74LVC541A level shifters (5 x $0.36). You could have a header or an edge on the top for programming. Nothing special, j...
by Chilly Willy
Tue Oct 02, 2018 10:00 pm
Forum: Hardware
Topic: Second Dimension PCB's
Replies: 6
Views: 385

Re: Second Dimension PCB's

Not as bad as some of those Chinese boards that hook 3V memory straight to the edge, but not as good as using level shifters.
by Chilly Willy
Fri Sep 28, 2018 1:29 pm
Forum: Controls
Topic: Mega Mouse Usage
Replies: 21
Views: 3665

Re: Mega Mouse Usage

Just posting an update on the Dune mouse patch. Here's my current code to read the mouse. Of note, it assembles (using asmx) to 58 bytes smaller than the original code (400 bytes vs 458) and handles overflow and sign properly. Tested on my Model 2 Genesis + Model 2 CD + 32X with both a Japanese Sega...
by Chilly Willy
Sun Sep 23, 2018 1:19 am
Forum: Megadrive/Genesis
Topic: 68k edge case: btst dN,#immed
Replies: 11
Views: 632

Re: 68k edge case: btst dN,#immed

btst has no opsize as it's defined within the instruction. btst on register is always a long, and btst on memory is always a byte. btst.anything is not correct syntax and I'm surprised the assembler accepts it. You get the same output because the assembler is at least ignoring it.
by Chilly Willy
Mon Sep 17, 2018 5:53 pm
Forum: Controls
Topic: Mega Mouse Usage
Replies: 21
Views: 3665

Re: Mega Mouse Usage

It drifts because it doesn't handle the sign bits for the mouse. It also doesn't check for overflow, but that's probably not an issue most of the time. Here's how it handles x and y move.w ($FFFFBF14).w,d1 move.b d0,d2 ext.w d2 asr.w #1,d2 sub.w d2,d1 cmpi.w #$D0,d1 ble.s *+6 move.w #$D0,d1 cmpi.w #...
by Chilly Willy
Mon Sep 17, 2018 5:15 pm
Forum: Hardware
Topic: Some questions about Saturn HW
Replies: 25
Views: 3065

Re: Some questions about Saturn HW

The SH2 isn't rated for higher than the "fast" Saturn clock. Any more than that may fail depending on the chips in the unit. I have no experience with how much the SH2 can be overclocked. Given the Saturn pushes the high end of the rating, I doubt many will overclock much if at all.
by Chilly Willy
Wed Sep 05, 2018 10:13 pm
Forum: Controls
Topic: Mouse range
Replies: 1
Views: 1045

Re: Mouse range

If overflow is ever set, you ignore x or y (depending on which overflowed), and use +/-256. The sign bit is separate from x and y, so they're actually 9-bit ranges, so -256 to +255. Here's how I process the mouse packet in Wolf32X mousebuttons = (val >> 16) & 15; mx = (val >> 8) & 0xFF; // check sig...
by Chilly Willy
Tue Sep 04, 2018 4:55 pm
Forum: SGDK
Topic: SGDK and tilemap-editors
Replies: 10
Views: 1163

Re: SGDK and tilemap-editors

Maybe have an option to turn off tile optimization for people doing conversions where they know they don't need it?
by Chilly Willy
Tue Sep 04, 2018 4:54 pm
Forum: Demos
Topic: Tänzer, a "ninja" game (Dev Diary thread)
Replies: 234
Views: 17767

Re: Tänzer, a "ninja" game (Dev Diary thread)

Dang! That video capture is sweeeeet!
by Chilly Willy
Wed Aug 15, 2018 7:01 pm
Forum: Announcement
Topic: Little Medusa now available on Genesis
Replies: 3
Views: 1038

Re: Little Medusa now available on Genesis

Neat game. It was a minor hassle getting the free demo, but it's a pretty cool puzzle game. You might get more of a response if you made a simple download link available rather than forcing people to "buy" the download for $0.00.
by Chilly Willy
Sat Aug 04, 2018 1:20 am
Forum: Demos
Topic: Tänzer, a "ninja" game (Dev Diary thread)
Replies: 234
Views: 17767

Re: Tänzer, a "ninja" game (Dev Diary thread)

START + button is easy... if you push start with the other thumb and the buttons like normal. You just have to let off the dpad for an instant. On a stock 6 button, MODE is the perfect selector button as it's on the right shoulder. Of course, on the 6 button, you probably don't need the selector. Th...
by Chilly Willy
Thu Aug 02, 2018 1:06 pm
Forum: Demos
Topic: Tänzer, a "ninja" game (Dev Diary thread)
Replies: 234
Views: 17767

Re: Tänzer, a "ninja" game (Dev Diary thread)

You could always make START a qualifier for the other buttons. START+A = pause, START+B = change specials one direction, START+C = change specials the other way. Being able to shift special attacks/weapons both ways allows for quickly flipping between specials, whereas only having one means having t...