nesdev.com

The section with the channel switch (or whatever it is) and the resistor and potentiometer next to the switch is looking rusty. If the potentiometer or switch aren't getting contact... that might cause nonsense channel selection. RF output has kindy terrible quality (and channel searching is kinda t...

Using multiplel loops, one that defaults to clipping, one that defaults to partial clipping, and one for complete clipping? That, with the conditional jumps jumping to the other loops when needed, and otherwise staying in the current loop. Doing that with completely unrolled loops would take up a lo...

Using 64x32 tiles per BG for horizontal scrolling is wasting 8Kbytes of VRAM (when doing it on all four BG layers), and it's a bit uncomfortable to update tiles in two map-halves... but it might be within scope.

That happens only if the controller is connected, and without pressing any buttons? Normally the controller should output 8 high bits in that case (same as when no joypad connected at all) (however, with the controller connected, you'll get low bits after the 8th bit). One guess: The joypad doesn't ...

Test 2 Light stays on (On both tests) That sounds worrying, and it's normally not possible at all, LEDs should light up only one way around. One explanation would be that you have repeated the same test twice, without swapping the pins. Or otherwise... you might have some more than terrible noise o...

Could WRAM be replaced by SRAM? Since CART regions can be set to be accessed at ~3.58 MHz... Theoretically, but the default SRAM mapping is... HiROM ---> SRAM at 30h-3Fh,B0h-BFh:6000h-7FFFh ;small 8K SRAM bank(s) LoROM ---> SRAM at 70h-7Dh,F0h-FFh:0000h-7FFFh ;big 32K SRAM bank(s) Fast memory could...

ADC does also affect the N flag, and also the C flag, that would work for overrun checking, too. Btw. if INC is meant to be short for INC A... then CLC+ADC+INC would be same as SEC+ADC. When using double buffered brightness values, instead of setting "current=new", you could update them as "current=...

I think it is ANY priority. Only thing that matters is the top-most main screen pixel, and top-most sub screen pixel (but doesn't matter if the main screen is in front of sub screen, or vice versa). Intuitively you would want to have the transparent layer in front of the other layer, but the color m...

Thinking about grid-free player movement with gridded blocks. That could look as shown below. It's using two simple rules: When pushing a block north, 1) player must be heading north +/-45 degrees 2) player must be within +/-40 percent of the block width If that isn't the case, ignore the vertical m...

Didn't happen to me in the above post, too. But it's happening in all my other posts here today. Maybe it's just my browser starting to act weird. The preview is bundled with this message "At least one new post has been made to this topic. You may wish to review your post in light of this." Although...

Here are two ideas about allowing rotation steps smaller than 90 degrees (without changing the grid-based game logic): 1) Rotate in smaller steps (while dpad left/right are held down), but align to the closest 90 degree direction when walking (via dpad up). That's probably not so good (as having to ...

I have found a secret passage: Go to one of the first two armors (the one with the vertical line and curved line in lower right). Walk about 150 pixels right. Then slowly walk back and forth a few times until falling through the hole in the floor. The floor in the underground passage is uneven (so y...

When submitting posts, I am now getting sent to the preview screen, which is prompting me to edit or submit the post. That happened twice today.
Despite of the preview, the post was submitted (if I submit it again, I end up with a double post, and have to delete the second post).

Before randomly buying new components, another step back: use fresh batteries (if you didn't already try that).
I would recommend the "Use-a-LED-instead-of-a--Multimeter" trick only if you are really completely unable to figure out how to use your multimeter.

Looking into a Vram Viewer, there seems to be a 2-dimensional array of 16x10 tiles (representing a quarter-circle) for the shadow mask. But each tile is having only a single brightness (instead having tiles that fade from upper-left bright to lower-right dark). So you could as well use a 1-dimension...