Jump to content

Daedalus2097

New Members
  • Content Count

    38
  • Joined

  • Last visited

Community Reputation

14 Good

About Daedalus2097

  • Rank
    Space Invader

Contact / Social Media

Profile Information

  • Gender
    Male
  • Location
    Glasgow, Scotland
  1. Most games aren't all that fussy about Kickstart versions - it must be really old games that you're having trouble with. Anyway, there isn't a version of KS 1.3 for the CD32, but degrader software that loads KS1.3 from disk and uses it instead should work just fine. It'll take up some RAM, but the CD32 already has more than a standard 1.3-era machine so that shouldn't be an issue. Check out Relokick for example. As for the PAL/NTSC thing, I'm not sure if the CD32 will retain its setting when Relokick is used. Games I've seen tend to be either PAL or NTSC based on where the publisher was from, but even most PAL games typically run on a 200 pixel screen instead of 256, so they work on both formats. I don't know of a comprehensive list anywhere - the two main games databases (HOL and LemonAmiga) don't carry video format tags. For a bit more investment, perhaps a mass storage solution could be useful for you. That would let you run WHDLoad, which patches most games to run from hard drive on newer Kickstart versions and eliminates all the floppy disk loading times and disk swapping...
  2. Just to add a little to this. Electrolytic capacitors are generally used with a safety margin, and their lifespan is affected by this. Typically, 2-3x the normal operating voltage is used - plenty of headroom and greatly extends the life. But going higher with the rating doesn't make it "safer" - as was already explained, they're not in any danger of being unsafe running on 5V. Given that the 16V parts involved have lasted 35-40 years at this point, how much safer do you really think they'll get at 25V? You're into the sort of territory where shelf life is a more significant factor than use, and 40 years is a perfectly adequate shelf life for such parts. But another factor that you haven't considered is that traditional electrolytics also need a reforming voltage in order to keep their dielectric in good order. Without it, the capacitor will slowly deteriorate, losing capacitance and gaining ESR. Ideally, this voltage should be as close to the rated voltage as possible, but when in-circuit, this obviously isn't the case. The effect diminishes the further you go from the rating, which means that going for much higher ratings effectively shortens their life spans. So, any perceived "safety" benefits or lifespan increases you get from changing from 16V to 25V parts is likely offset by depriving the capacitor of more of the reforming voltage it needs for a long life.
  3. I'm using an official Raspberry Pi PSU with a new connector for my 800XL (also using a 1084 monitor and Y/C video - excellent picture!), which is available for a few pounds and is specced for the same load as the original PSU. If you wanted to keep the ingot-style PSU however, there are lots of small industrial PSU modules used for all sorts of equipment that could be fitted inside the case. One example is the Mean Well RS-15-5, which gives 3A output.
  4. Yep, if you're changing the type of regulator, the support circuitry should probably be adjusted for the different characteristics. If the PSU is designed for a 7805, it will have the correct capacitors in place to ensure the output is stable for that type of regulator. Check the datasheets of the other types of regulator to see application notes for what additional circuitry is required and add it (r modify the existing circuitry) - that should eliminate any noise you get from it in the video or audio output. It could be as simple as replacing one capacitor with a different value. Depending on the multimeter, you might not get an accurate reading of ripple, as modules like that typically use switching in the 2- or 3-digit kHz range, which may be beyond the capabilities of the meter to measure. The 78S05 won't be much cooler than a standard 7805 - the amount of energy to dump as heat is the same, and they're in the same package, so it all comes down to the heatsink used. But it won't burn out as easily when it's run close to 1A. There's also a H version that's rated for 5A, but it's in a different package and is intended to be mounted on the heatsink (rather than the heatsink mounted on the chip), so would require some fudging to physically fit it.
  5. I've never heard of one, or a game that supports one. The theory is sound, since those same pins are used for 3-button mice (which did exist but were rare back in the day), but many developers were still firmly stuck in the old one-button mentality up until the CD32. Even then, many CD32 games were simply older A500 versions stuck on a CD, so only support one of the CD32 controller buttons...
  6. For a modular PSU, you could use something similar to PC modular supplies - a set of Molex Mini-fit Jr connectors flush mounted on the front (clicky for example). These are cheaper than heavy duty threaded DINs, and have locking lugs to hold them secure, though they need to be board mounted so a little creative bracketing might be needed inside the case. If I was going to do it, I wouldn't use one of the AC supplies for the 5V rail, since that could load it down quite a bit. I'd fit a separate mains-powered module that can also supply 12V (and maybe -12V too for Amiga use). I like the idea of having a standard connector for everything - maybe a 6-pin Molex - and only populate the pins needed for the particular supply you're using. Including a couple of USB sockets is never a bad idea - so many things can use them.
  7. Not especially, no. I would have the box ventilated as any PSU of a similar power (add the various power ratings together to get an overall figure), but those transformers themselves don't generate a lot of heat unless they're being pushed hard. I would keep all the outputs in phase, just in case some of them end up connected in parallel, but I expect that's not generally possible.
  8. Yep... But if you're building a custom PSU into an enclosure anyway, why not just fit as many discrete transformers as you like? Twin secondary 9V transformers are available off the shelf (for example, 2x9V 1.5A secondaries), so for 4 isolated outputs you only need 2 transformers. Add a Mean Well module (for example, 5V 4A & 12V 2A), and there you go - high quality 5V and 12V DC outputs, and multiple, isolated 9V outputs.
  9. Just a thought here, but what about putting a switch between the capacitor and the RPi? That way, when you want to actually turn off the machine, you can isolate the RPi, leaving the charge in the capacitor there so it'll take less time to fully charge the next time you use it. Might seem a bit of extra faff, but could help if the half a minute charge time becomes an issue.
  10. AC/DC differences alone won't make the difference here. If it's possible to have multiple devices connected individually with their own PSUs and have no ill-effects, it will be possible to power them from a single PSU. It might need some additional consideration, like separately switched outputs, but it will be possible with a small amount of work. Worst case scenario, an AC supply with multiple isolated outputs is pretty trivial to build. Yeah, I'm using a couple of official raspberry Pi power supplies for my Atari 800XLs, Working great! PC PSUs are massive overkill for 8-bit stuff. Especially newer ATX PSUs, which might be dangerous to use with such low loads as they're built to expect a minimum load of dozens of watts. There are plenty of cheap industrial PSU modules by the likes of Artesyn, Mean Well etc. that would be better suited to lower loads, as well as being smaller.
  11. Yep, it's pretty straightforward to create your own components in Eagle too (or, at least 7, which is the latest version I've used).
  12. Having recently rescued a couple of 800XLs from my parents' attic, the first thing that immediately came back to me was the poor keyboard connections, which I remembered gave me a lot of grief as an experimental child. And, sure enough, my original machine shows where the mylar had cracked, and where I had bypassed the bad traces with some crudely soldered wires. Naturally, it was unreliable at best, and it means my function keys don't work most of the time. I was actually thinking of replacing the connector with a pin header, and the cable with a proper ribbon cable running to another pin header on the keyboard itself. I can keep the original friction connector in case I ever feel the need to replace it in the future...
  13. The numbers at the edge of the box will be the pin numbers of the chip. Schematic diagrams will order the pins in a logical layout, rather than a physical layout. In fact, the entire schematic will also be a logical layout that doesn't represent the physical layout of the circuit. This makes it easier to follow signals and understand the operation of the circuit. The labels inside the chip represent the signal names. A0-A15 are the 16 address lines, D0-D7 are the 8 data lines, Vcc and Vss are the power supply, and then we get more specific. NMI is typically Non-Maskable Interrupt, RST is Reset, R/W is whether the bus is being read or written (usually CPU relative), HALT is an all-stop signal, usually because of a serious fault detected, unhandled interrupt, taking control of the bus from the CPU or similar. RDY is Ready, usually used to indicate that the bus is ready to start a requested transfer, or to move onto the next step of a transaction. AN0-AN2 are the three signals of a special ANTIC bus on Atari 8-bits, which are used for direct transfers between the custom chips without getting the main CPU bus involved, and are typically used during the building of the display. 0O and F0O are clock signals. A bar above any signal name indicates that it's active low, i.e. it is asserted by dropping the signal level to close to 0V. The general descriptions above could be improved with some specific context. I'm not particularly familiar with these systems so I can't offer much more than that.
  14. Yeah, the audio caps are installed backwards on many CD32s, but the other electrolytic capacitors in general will all need to be replaced at this stage, since they're the awful SMT types and will leak and damage the board. The keyboard port (aux) on the CD32 itself will only work with Amiga keyboards - the A4000 one has the same connector, all of the others can be connected with a simple adaptor). The SX-1 can take a normal, old-style PC keyboard - either AT directly or PS/2 using a simple adaptor you can find for a couple of quid. This is by far the cheapest option if you don't already have an Amiga keyboard lying around the place, though the key mapping won't be 100% since there are a couple of differences (e.g. no Help key on a PC keyboard). In particular, it predates the introduction of the Windows keys so I'm not entirely sure how you can access the Amiga qualifier keys, though it's mostly applications that will use them.
  15. A bit late to this, but I don't remember there being any such control in the Amiga version. I do remember that J was the key for the in-system jump (between when you entered a system from hyperspace and when you are within range of the planet). I seem to remember reports that the Amiga and ST versions were written from scratch without the original source code, so that could explain the missing feature.
×
×
  • Create New...