One thing that I remember vividly was you had no MUL or DIV, so you have to implement them yourself with shifts, adds, subtraction, etc. This was an extremely useful learning experience
Do you think you could remember most of Z80 ASM? I looked at some old ASM I wrote long ago, and it's hard to follow the logic of the program, since most lines are messing around with the registers. But basics like 'ld hl,xyz' and 'jp/jnz' still make sense.
I find when you learn things at 15 they tend to stick around. (Stuff I learned last week, not so much!) Even just looking at your example, I remembered that HL is a 16 bit register and you can split it into two 8 bit registers H and L if you want. I think most of it would come back; I wrote quite a lot of it, both for the TI-83 and later for a Z80 that I bought and put on a breadboard and wired up to some RAM and EEPROM, about as bare metal as it gets.
> most lines are messing around with the registers
Isn’t that just the nature of assembly? :)
>Kerm Martian
There's some names I haven't heard in a while :)
This is substantially inaccurate.
1) Not all ARM Cortex series CPUs have TrustZone. It is absent on many Cortex-M microcontrollers, for example.
2) TrustZone is an operating mode of the CPU, not an "admin processor". Depending on the part, it is often made accessible to developers. (Whether that includes third-party software developers is, of course, up to the device manufacturer.)
For more information, see:
https://developer.arm.com/documentation/100690/0200/ARM-Trus...