Search found 3123 matches
- Fri Feb 16, 2024 2:42 pm
- Forum: Games/Software
- Topic: How big should new Speccy games be? 48k? Bigger? Release 2 versions?
- Replies: 67
- Views: 1751
Re: How big should new Speccy games be? 48k? Bigger? Release 2 versions?
Oh, and I feel that the small minority with an "80K" RAM upgrade are being left out :cry: Technically it is also possible to have a 32K Speccy (16K rubber key with 16K of expansion RAM). I don't know if anyone ever made expansion packs or fitted suitable DRAM chips internally for this thou...
- Fri Feb 16, 2024 2:38 pm
- Forum: Games/Software
- Topic: How big should new Speccy games be? 48k? Bigger? Release 2 versions?
- Replies: 67
- Views: 1751
Re: How big should new Speccy games be? 48k? Bigger? Release 2 versions?
Yeah but, no, but... Are we speaking about "straight" AY sound chip data, music notation, samples or what? 6K bytes of AY sound chip music data <> as data for samples. Then there is the mass storage system being used. Real tape LOADing on a real ZX Spectrum is rather slower than being LOAD...
- Thu Feb 15, 2024 7:55 pm
- Forum: Website
- Topic: Forum e-mail alerts corrupted?
- Replies: 7
- Views: 242
- Thu Feb 15, 2024 4:30 pm
- Forum: Hardware
- Topic: Cant load anything
- Replies: 41
- Views: 1140
Re: Cant load anything
No problem.
It's a lot easier when a DRAM chip fails and produces a binary 1 regardless. When they produce 'random' outputs or bianry zeros, it's a bit more tricky.
Mark
It's a lot easier when a DRAM chip fails and produces a binary 1 regardless. When they produce 'random' outputs or bianry zeros, it's a bit more tricky.
Mark
- Thu Feb 15, 2024 2:57 pm
- Forum: Games/Software
- Topic: How big should new Speccy games be? 48k? Bigger? Release 2 versions?
- Replies: 67
- Views: 1751
Re: How big should new Speccy games be? 48k? Bigger? Release 2 versions?
And artists are often capricious people ;) They may draw some stuff that won't fit you from a coding point of view, as the others said. If you tell them to redraw it, they will get offended and leave. That's it, I'm done with this, I quit, you can finish this topic on your own... :twisted: Mark PS ...
- Wed Feb 14, 2024 11:18 pm
- Forum: Hardware
- Topic: Cant load anything
- Replies: 41
- Views: 1140
Re: Cant load anything
strangely the speaker makes no sound when i connect the meter - still reads 39 ohm , the diaphram looks good , moves nicely - does not appear to be held up from vibrating , but no noise - can i put 5 volts into it ? Err, not if you want it to work after. Wire a 220Ω or similar resistor in series to...
- Wed Feb 14, 2024 11:11 pm
- Forum: Games/Software
- Topic: How big should new Speccy games be? 48k? Bigger? Release 2 versions?
- Replies: 67
- Views: 1751
Re: How big should new Speccy games be? 48k? Bigger? Release 2 versions?
So… I was doing some AY music for an upcoming game by @gabriele amore. The actual game is under 48k, so I figured I'd have over 80k for the music, since it can only play on 128k machines. :shock: Oi! My AY card for the rubber key / + Speccy says otherwise... :dance As this is a hobby, I went for op...
- Wed Feb 14, 2024 9:23 pm
- Forum: Hardware
- Topic: Cant load anything
- Replies: 41
- Views: 1140
Re: Cant load anything
I will be replacing every cap in the machine Just the electros I presume? Apart from C5 to C8 I mentioned above, the ceramics don't normally cause any problems. took the speaker out , getting 39 ohms across the terminals , from reading , thats good Yes. Does it click if you tap a meter lead as you ...
- Wed Feb 14, 2024 7:55 pm
- Forum: Hardware
- Topic: Cant load anything
- Replies: 41
- Views: 1140
Re: Cant load anything
I feel your pain. Buying items from abroad is now a right pain. The U.K. leaving the E.U. has not helped. The real problem is IMHO called VAT. But let's not get into politics. Else we will get into trouble (in this forum, talking politics is almost taboo). The owner of Retroleum is very helpful. But...
- Wed Feb 14, 2024 6:04 pm
- Forum: Hardware
- Topic: Cant load anything
- Replies: 41
- Views: 1140
- Wed Feb 14, 2024 6:02 pm
- Forum: Hardware
- Topic: Cant load anything
- Replies: 41
- Views: 1140
- Wed Feb 14, 2024 5:42 pm
- Forum: Hardware
- Topic: Cant load anything
- Replies: 41
- Views: 1140
Re: Cant load anything
Post above edited.
- Wed Feb 14, 2024 5:40 pm
- Forum: Hardware
- Topic: Cant load anything
- Replies: 41
- Views: 1140
Re: Cant load anything
So, I'm back :!: :P :lol: For a replacement chip, you either need a TMS4532 - 15NL3 (which are long out of production and nearly as rare as a live Dodo). Or a 4164 DRAM chip, preferable a Texas Instruments (TMS) one. Although various other makes will work as well. If you find any or intend to buy so...
- Wed Feb 14, 2024 3:59 pm
- Forum: Hardware
- Topic: Cant load anything
- Replies: 41
- Views: 1140
Re: Cant load anything
Yes, different DRAM chips are used for 'lower' and 'upper' RAM. 4116 are not suitable to replace a upper DRAM chip.
Be back later, as the site is about to go off-line...
Mark
Be back later, as the site is about to go off-line...
Mark
- Tue Feb 13, 2024 11:16 pm
- Forum: Games/Software
- Topic: C.S.S.C.G.C 2024 is/will be/has open/ing/ed
- Replies: 102
- Views: 4596
Re: C.S.S.C.G.C 2024 is/will be/has open/ing/ed
H2G2 detected
Mark
- Tue Feb 13, 2024 9:36 pm
- Forum: Hardware
- Topic: Making a Scalextric lap counter
- Replies: 20
- Views: 589
Re: Making a Scalextric lap counter
Thanks Mark, I believe using my multimeter I can identify the base so I will just use that as the reference point and hope for the best. Oh no, you don't get off that easy.... https://youtu.be/nCryJU2sh3c?si=olLFSk2XCuEBt19D https://i.postimg.cc/Y4Nmqy8T/IMG-7800.jpg https://i.postimg.cc/c6hMc6RP/I...
- Tue Feb 13, 2024 4:30 pm
- Forum: Hardware
- Topic: Making a Scalextric lap counter
- Replies: 20
- Views: 589
Re: Making a Scalextric lap counter
I'll get a real one out later and take a photo.
Mark
Mark
- Tue Feb 13, 2024 4:28 pm
- Forum: Hardware
- Topic: Cant load anything
- Replies: 41
- Views: 1140
Re: Cant load anything
the replacement must either be the exact correct 32K DRAM chip. Or a 64K DRAM chip that has the same row/address layout.
Mark
Mark
- Tue Feb 13, 2024 7:00 am
- Forum: Hardware
- Topic: Cant load anything
- Replies: 41
- Views: 1140
Re: Cant load anything
So, the reason for those test values is because we really want four different binary test patterns. With the RAM in a Spectrum, it's divided into the 'lower' RAM and the 'extension' or 'upper' RAM. The 'lower' RAM runs from 16384 (0x4000) to 32767 (0x7FFF). The 'upper' RAM runs from 32768 (0x8000) t...
- Mon Feb 12, 2024 10:26 pm
- Forum: Programming
- Topic: That thing with the bottom two lines
- Replies: 19
- Views: 806
Re: That thing with the bottom two lines
It's a hang over from the ZX80 (which only had a 4K byte ROM). The ZX81 ROM built on the ZX80 ROM (now 8K bytes in size). Then the ZX Spectrum ROM is a development of the ZX81 ROM... Sinclair wanted maximum features for lowest cost (read keep something that worked, and make everything fit in only 16...
- Mon Feb 12, 2024 9:02 pm
- Forum: Hardware
- Topic: Making a Scalextric lap counter
- Replies: 20
- Views: 589
Re: Making a Scalextric lap counter
Here's a circuit simulation. Because it does not include a potentiometer, I've used a fixed resistor. Also not included is a LDR, so I have used a clickable logic level input (swaps between L and H) a diode and a fixed resistor. This very crudly simulates day/night as if there was a LDR. https://www...
- Mon Feb 12, 2024 8:30 pm
- Forum: Programming
- Topic: 128K beyond the 'Introduction' pamphlet
- Replies: 13
- Views: 477
Re: 128K beyond the 'Introduction' pamphlet
Let's play spot the difference! Front cover #1 https://i.postimg.cc/fJMrGVvq/IMG-7768.jpg Front cover #2 https://i.postimg.cc/KKrFcVRr/IMG-7769.jpg So which is for the +2 (grey) and which is for the +2A / +2B? Maybe a side view would help... https://i.postimg.cc/CBBNsykb/IMG-7775.jpg Okay, I'll open...
- Mon Feb 12, 2024 8:03 pm
- Forum: Programming
- Topic: 128K beyond the 'Introduction' pamphlet
- Replies: 13
- Views: 477
Re: 128K beyond the 'Introduction' pamphlet
For the 128K, the +2 (grey) manual is useful. It includes a big, big chunk of the original ZX Spectrum rubber key manual. Not to be confused with the later manual for the +2A/+2B machines which are different again.
Mark
Mark
- Mon Feb 12, 2024 7:44 pm
- Forum: Hardware
- Topic: Making a Scalextric lap counter
- Replies: 20
- Views: 589
Re: Making a Scalextric lap counter
Don't confuse the diode like effects when testing a bipolar transistor like a BC108 with how it actually works when used in an amplifier or switching circuit. The transistors operation is far more complex. In this circuit, the transistor is used as a common emitter amplifier. The 100kΩ potentiometer...
- Mon Feb 12, 2024 6:00 pm
- Forum: Hardware
- Topic: Making a Scalextric lap counter
- Replies: 20
- Views: 589
Re: Making a Scalextric lap counter
Transistor lead outs are always viewed from below unless stated otherwise (this is opposite to IC/chip pin outs which are viewed from above). Yes, a BC108 is a NPN. And yes the emitter is the lead next to the tab. The middle lead is the base, leaving the remaining lead as the collector. The data-she...