16-bit increment/decrement circuit of
- The 8-bit Z-80 processor was very popular in the late 1970s and early 1980s, powering many personal computers such as the Osborne 1, TRS-80, and Sinclair ZX Spectrum. It has a 16-bit incrementer/decrementer that efficiently updates the program counter and stack pointer, as well as supporting several 16-bit instructions and memory refresh. By reverse engineering detailed die photographs of the Z-80, we can see exactly how this increment/decrement circuit works and discover the interesting optimizations it uses for efficiency.
- Tuvalu (Wikipedia)
Tuvalu (/tuːˈvɑːluː/ too-VAH-loo) is an island country in the Polynesian subregion of Oceania in the Pacific Ocean, about midway between Hawaii and Australia. It lies east-northeast of the Santa Cruz Islands (which belong to the Solomon Islands), northeast of Vanuatu, southeast of Nauru, south of Kiribati, west of Tokelau, northwest of Samoa and Wallis and Futuna, and north of Fiji.