I could hold the whole 6502 instruction set (and their cycles) in my mind while programming, it was that simple.
I acquired a Z-80 softcard for my Apple ][ (for trying out CPM) and was flabbergasted by the expanded register set, the complexity of some instructions (e.g. DJNZ) and the fact it ran at 4MHz vs 1MHz for the 6502 (got a speed demon 65C02 card later). However I couldn't keep all instructions and timings in my head. Speedwise the 1MHz 6502 and 4MHz Z80 were on par.
I preferred, however, the fact that I/O was memory mapped on the 6502.
> Speedwise the 1MHz 6502 and 4MHz Z80 were on par.
This is a bit of an exaggeration, the 6502 was efficient but not that efficient. While generally understood that the Z80 took 2x-4x ticks to execute instructions as the 6502, in the real world its larger register set meant properly-written Z80 code could avoid expensive, slow round trips to memory.
Outside of artificial benchmarks real world performance shows that the 6502 is roughly 2x as efficient per clock cycle as the Z80[0], i.e. a 1 MHz 6502 is approximately equivalent to a 2 Mhz Z80.
This is reflected in the computers of the day, i.e. TRS-80s were not being blown out of the water by Commodore PETs.
Well, of course the idea of DJNZ was to implement a very common pattern (decrement a register and jump (normally backwards) if the result was not zero) - this tended to simplify code rather than make it more complex.
> However I couldn't keep all instructions and timings in my head.
I was never really interested in the timings, but I did get to the stage (not by conscious memorisation) of being able to assemble and disassemble Z80 code in my head, with some accuracy.
> I preferred, however, the fact that I/O was memory mapped on the 6502.
Many (most?) Z80 systems used memory mapped I/O. It's down to the hardware designer.
> I did get to the stage (not by conscious memorisation) of being able to assemble and disassemble Z80 code in my head, with some accuracy.
Same here.
I never got any fluency using EXX and the shadow registers - there were so few situations it was worth the effort. I always felt like I must be missing something.
I suspect the shadow registers were there to improve interrupt handling, reserve their use exclusively to an interrupt handler, and you could save time in not having to store registers in memory.
That, or in general for system calls. In particular EX AF,AF' + EXX allowed you to exchange all registers other than AF, to be able to return an error code or status.
> I preferred, however, the fact that I/O was memory mapped on the 6502.
The Z80 could do memory mapped IO as well of course (used at least in some arcade machines), but why waste valuable address space when there's an entire 64 KB of extra address space reserved for IO ;)
I'm a 6502 guy myself, but the Z80 instruction set is also easily holdable in one's memory.
As others said, a 4MHz Z80 is clearly capable of outperforming a 1MHz 6502 as is evidenced by the many ZX Spectrum demos that show off 3D/plotting effects.
It's hard to say otherwise. They were moderate left in the 80s when they were doing nationalizations and pro-worker reforms. They've embraced free market in the 90s which is arguably not very left-wing. Leaving aside same-sex marriage for a minute, Hollande's rule was well-known for social regressions for workers (Loi travail) and minorities (Déchéance de nationalité, taking 7 year-old children into police custody for thought crimes), and handouts for wealthy elites (CICE). That, and systematically continuing to destroy public services that Sarkozy already harmed. That can hardly be called left-wing in my book... unless you'd like to name left-wing policies introduced under Hollande?
Hollande?
Exemption for capital gains on investment property pushed from 15 to 30 years retention.
Repelled sarkozys state financing tuition for French schools abroad.
Many other examples that no self respecting right wing politician would promulgate.
Hollande was (is) socialist.
Takeover of half of Papua New Guinea, now called irian Jaya.
Transmigration, that is, moving Java people there and to Borneo (Kalimantan)in order to flood local populations with Malays.
But this did not make the news that much. Not that interesting I guess…
>Iga Swiatek (the tennis player) was denied entry in the player area for her own match. Situation was quickly resolved.
>I doubt VIPs go through the same entrance, lines and checks as regular folks.
For those of you unfamiliar with professional women's tennis, Swiatek is currently ranked #4 in the world and to date has spent 125 weeks as the #1 women's tennis player in the world.
For example, multicore OCaml is not free of race conditions.
The GC, while super efficient (pauses are in the milliseconds), is not suitable for hard realtime.
Still, where absolute max performance or realtime are not required, I'd choose OCaml as it is elegant & a pleasure to code in (personal opinion, ymmv).
I didn't think of the gun getting passed around. To me, "one round" is pulling the trigger once after spinning the cylinder with one bullet. 1-in-6 chance of dying, you'll probably live. That's how I feel about this mission, I think they'll probably live, but man I'm nervous.
Not parent, but I am genuinely curious: is there a Hacker News browser extension you'd recommend? The text is so small by default that even though I'd like to read on my desktop, I typically only browse it via the Hacki android app.
I vibe-coded one using one of the web-based tools (I think Replit?) maybe a year and a half ago. Just added vote tracking by username, tagging, colored usernames, that sort of thing. Only took a on average 1-2 prompts per feature, I did it in under an hour start to finish.
I acquired a Z-80 softcard for my Apple ][ (for trying out CPM) and was flabbergasted by the expanded register set, the complexity of some instructions (e.g. DJNZ) and the fact it ran at 4MHz vs 1MHz for the 6502 (got a speed demon 65C02 card later). However I couldn't keep all instructions and timings in my head. Speedwise the 1MHz 6502 and 4MHz Z80 were on par. I preferred, however, the fact that I/O was memory mapped on the 6502.
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