Hot answers tagged

51

They were different. You probably already know that NTSC is 60 Hz and PAL is 50 Hz. The video generation hardware was much more 'bare metal' than today (the NES color palette implementation was so bare metal that one of the colors you could select, referred to as 'blacker than black', could mess up some TVs due to the way the NES simply fed the color bits ...


28

The NES's region lock is implemented in hardware, not software, with the CIC chip. The NES contains a CIC, and each authentic cartridge contains an identical CIC. When the console is powered on, the two chips communicate via a challenge-response handshake protocol, and if the cartridge fails to provide the correct responses, the CIC on the NES resets the ...


17

The PAL video encoder was not a bottleneck of any kind. It is left out because the unit is not a PAL model, but a SECAM model, which needs a different kind of encoder. So the chip is not needed and it would be useless and just cause extra cost and power consumption in the SECAM model. The necessary SECAM encoder is integrated to the separate board with the ...


16

Basically the difference between PAL and NTSC consoles is the frame rate, 50 vs 60 Hz. The consequence of that is that PAL and NTSC mostly differ in number of cycles available for the CPU per frame, with NTSC numbers being significantly smaller. More subtle differences might be number of cycles per scanline, position of visible screen area related to the ...


14

In the early 80s, cost of RAM for the framebuffer was the dominant factor, closely followed by RAM bandwidth. The difference in resolution between NTSC and PAL systems is minimal in comparison to these factors (note that despite the different number of lines per field and different field rate, each technology used a very similar line rate of ~64us per line, ...


12

I had two micros when I was growing up: the SAM Coupé and the Acorn Electron. The SAM Coupé has a 512x192 mode much like you discuss. The SAM's display is physically wider than a Spectrum's though, pixels being approximately 1.25 times as wide as tall. The Acorn Electron inherits full 80-column 640x256 video from its progenitor, the BBC Micro. In both ...


11

Yes, but only a very slightly different speed: the master crystal was around 14.238Mhz rather than 14.31818Mhz. which is only around 0.5% different, so I would expect safely within tolerance for a Disk II. Something PAL users didn't get from the base machine: colour. The relationship with phase is a lot more complicated in PAL, as that's how the error ...


10

Rather than convert the NES, just get a PAL monitor. The common auto backup video systems use an NTSC/PAL switchable monitor, available for not much money.Backup monitor 7" It is also possible, with some video capture cards, to select PAL (then your computer display will allow you to use the game). If your TV takes PAL input (some do: check all the ...


10

Technically, no, because usually hardware was fixed to generate the TV signal in a fixed way, instead of being programmable. Many systems had separate video chips for different TV systems, and due to the difference in the video timing or color encoding, also the clocks available in the system to run the CPU or audio chips varied. So basically, taken a NES as ...


9

What would be the ideal resolution? There is no "ideal" resolution. TV screens use "overscan", which means that the full TV image is occluded by a bezel. That doesn't matter for movies, but it does matter if you have text on the screen. So you need to choose a part of the image that would be inside the bezel of most TV models, because ...


9

You'll have to get a PAL to NTSC converter. A modification to make a PAL NES to output NTSC video would be extremely difficult because both the console and the games are designed for the video signal. The NES's clock frequencies were chosen to match the timing of the video signal, so you'd have to replace the clock circuitry. The PPU is hard-wired to ...


8

At startup, the Amiga used a timing routine to check the frequency of the AC power supply, and start in PAL (50 Hz AC) or NTSC (60 Hz AC) appropriately. Unfortunately, the detection was buggy, and sometimes 50 Hz was wrongly identified as 60. Many Europeans would have Declan McArdle's NoPALReset in their s:startup-sequence to avoid this. I think the problem ...


8

According to CPCwiki Oric-1 had something that made it unnecessary to have a SECAM UHF signal. It was (one of few) computers in that price range that had RGB out connector. This made it possible to connect the computer to a TV set through a SCART connector. This connector was widely used in France, although requiring an external power source (remanufactured ...


7

If this is about connecting the color computer to television antenna input via an RF modulator, then the local TV system variant matters, as both the RF modulator for the computer and the RF demodulator in the TV are built to use a certain composite video signal bandwidth. For a 625-line 50 Hz field rate TV system, the maximum composite video signal ...


5

Z80 and 6502 are complete different CPUs in terms of clock and cycle structure. There is no sense in comparing them at this level. To solve your problem you need to focus only on your Z80 system, its instructions and their timing in relation to the video frame you want to create/manipulate. With 4 MHz each clock cycle is 250 ns. Using this on 50 Hz 625 ...


5

Porting a game to PAL while making all actions take the same number of frames would cause the game to perform 20% slower than with NTSC. Some games did this, but other games adjusted the amount of distance objects could move per frame or reduced the number of frames required to perform various actions. Although some games could accommodate fractional-pixel ...


5

These answers are contradictory basically because none of them are getting down to the real meat of the issue. That is, it depends if the programmers accounted for it or not. The ease of doing this will also vary by console, as well as how severe the consequences if programmers didn't. Here are a few examples. (To simplify things I will generally assume that ...


4

I'll take PAL to mean the specific composite-video signal format for color TV, deliberately excluding higher-resolution versions like S-video with multiple signal lines (see Wikipedia). The vertical resolution is fixed by the signal timing of 625 interlaced scan lines, meaning that you can either use interlacing and get a maximum of 576 lines with a very ...


4

The resistor network output voltages do not match the optimal modulator input voltages, and they do not have to match, as long as the modulator input voltages are within the range. The antenna RF inputs of the TVs work under various signal strength conditions anyway, like due to range to various transmitting TV stations or good/bad weather conditions. So ...


4

An unmodified Amiga 500 provides two outputs: analogue and digital RGB through its DB23M connector monochrome composite through its RCA connector Colour encoding is identical in both PAL and NTSC variants on the RGB output, and not present on the RCA connector, so the vast majority of screens with the corresponding inputs will work fine with either (they ...


4

I can think of several options: The hardest one (because it is still WIP) is to remove the PAL ULA and get a NTSC ULA. NTSC ULA's existed for some clones intended for the American market. Today they are very rare chips. However, there are some projects that aim to design a direct replacement ULA using programable logic. These projects may support NTSC ...


4

Simple answer: Yes, they all do (plus many US HDMI TVs accept 50 Hz anyway). But you may want to check if they are able to process PAL input, as there are some (usually older) who don't. Also, there are differences in their upscaling algorithms, so while this is no big issue for a movie it might be annoying on certain consoles/games. So it might help to ...


3

A working power supply and a completely black screen hints to a memory problem in the lower banks or an MMU contact problem (which is way more likely with the computer traveling that far). The ST sees no memory at all and won't even display a (white) picture. I would first carefully remove the MMU from its PLCC socket and thoroughly but carefully clean the ...


2

You're never going to convert a 50 FPS to 60 FPS (or vice-versa) and have the game run perfectly...the way the designers meant it to run. It's always going to run too fast (PAL running on NTSC) or too slow with lag (NTSC running on PAL). The problem is the conversion itself. Think of two metronomes starting at the same time. One runs at 50 FPS and the ...


2

The easiest and cheapest solution is probably a composite to HDMI adapter that supports PAL. But it will add about 2 frames of lag (search in that link for "HDV 8S" for the review), so fast-paced games may be a little more difficult to play. The best solution for digital displays is either an HDMI NES mod or an XRGB-Mini Framemeister, both of which are ...


2

I had a Timex TC 2048 (compatible with the ZX Spectrum 48k) with the text extended modes, never used them much. Granted, they were not supported by the ZX Spectrum ROM in the first place and the software to support them was not that widespread; however I got a tasword copy that supported those modes, and in my cheap B/W (PAL) TV the result was difficult to ...


2

So, I am using 220V/60Hz instead of the European standard of 220V/50Hz. Which should be fine for most. Especially the ones with switching PS. Further 220V is fine, as they are old machines from back when continental voltage was 220 (and Brits still used 240). My question mainly concerns the Atari. I am getting 5V and 12V from the PSU, but no video or ...


1

PAL's (and NTSC's) main technical limitation is its number of scan lines. In theory, you have 625 lines to work with, but interlacing means that you'll probably want each pixel to be at least two lines high so that it's (partially) present on the screen at all times. And if you also figure that the top 10% and bottom 10% of the screen are off-limits as a ...


1

well I would use oscilloscope and look if: clock is running data and address buss is alive that can rule out CPU and MEMORY side problems. If working measure the modulator input/output if it produces signal. If yes the problem is either in cables or in the monitor itself. Otherwise you might have problem with graphics ICs. However take in mind I am not ...


1

If you checked output power of the power supply to be ok, then it is a problem of computer electronics. This Atari was reported to be working by the prior owner Do you think anyone would admit that? Problem may also happen during transportation. Anyway you need to find someone to take a closer look onto the boards and troubleshoot them. At first take a ...


Only top voted, non community-wiki answers of a minimum length are eligible