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Comment by notorandit | Hacker News Reader

It's a rather weird combination of year, CPU and memory.

Z80 is (still) an 8-bit CPU with 16-bit addressing. It cannot access more than 64kiB at a time. The hardware and the software needed to overcome that limit was worth more than an 8088/8086 (or compatible CPU) with MS-DOS and Telix.

In 1993,the age of 80286 and 80386, 8088/8086 were considered low-low-end CPUs, let alone the Z80, even in Mexico.

Not pointing my finger, just stating some facts.

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I'm pretty sure I wrote Z280 checking yep, the Zilog Z280 can address 16 MB of memory. It has separated MMU mapping for code and data (64K + 64K mapped anywhere) ideal for operating systems, but if you never enter this mode, then you can access at the same time 64K at the lowest memory address using the normal instructions, 64K using LDUP, and 64K using LDUD. Of course, you can update the MMU registers as required to access other memory spaces, I used the 8K page size. Besides the CPU has a small cache, so it was faster by a magnitude than a Z80.

Sorry, my bad sight tricked me.

Just as some perspective: in Uruguay in ‘93 things were still all over the place. I was still running an XT until about the end of the year, where we jumped straight to a 486 (alas… SX). And as late as ‘95 I had a classmate (who went on to graduate as both electrical and computer engineer) who was doing high school papers on a Spectrum.

ZX +3? If not, he was brave...

I don't remember the specifics but I can confirm he was brave :)

I know a local company at some point had a disk-drive-like interface to better use tapes (HiLow Datadrive) so maybe he had that, because saving work to cassette the way I saved things to cassette in the 80s would have been painful (not that it wasn't painful in the 80s of course!)

My recollection is it was basically the same computer he had since the 80s. I always have trouble identifying a specific sinclair version because I had clones (tk-90x, then tk-95).

It was a Z280, not a Z80. And apparently, the person's father's, who also bought and programmed some transputers. See the other posts in the series.

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