|
- How did the Z80 instruction set differ from the 8080?
The Zilog Z80 microprocessor, known for its use in the ZX Spectrum, was designed to be a backwards-compatible extension to the Intel 8080 processor It introduced several new instructions to the 8080's instruction set, as well as adding or extending registers
- Comparing raw performance of the Z80 and the 6502
The Z80's fastest memory fetch — the first half of an operation fetch — takes two cycles That's always paired with another two cycles for refresh though, so the shortest instructions are four cycles long Reads and writes that occur because the opcode tells them to generally take three cycles, though they're not always issued instantaneously
- z80 - What is R register and DRAM refresh internal operation . . .
The Z80 CPU has a built-in feature to support refreshing DRAM memory, by keeping a 7-bit refresh counter in the register R The refresh counter is increased by 1 after every instruction opcode fetch, and after the instruction opcode has been fetched and being decoded, the idle time on the bus is used to do a refresh bus cycle with the register
- Good Z80 disassembler decompiler on modern equipment?
I have previously played a bit with REZ (the Z80 version of RESOURCE) which was nice but I was wondering if there are better tools now 30 years later running on modern equipment
- z80 - Decoding Logic and Memory Systems for 8-bit computer - 64K . . .
8 I have solved a similar problem when reworking my 8085-based OMEN Alpha computer for the Z80 CPU The memory part is really simple: You have two memories, 32k each, and you should map the EEPROM from 0000h, RAM from 8000h I use common data and address bus, as well as the control bus ( RD and WR)
- What was the last commercial Z80-based computer sold?
AFAICT, the last Z80 desktop computer sold was the TRS-80 Model 4, in production until late 1991 If you include notebook computers, the Amstrad NC200 was released in 1993
- Did any computers use the Z80B? - Retrocomputing Stack Exchange
The Z80 was one of the most popular CPUs of the seventies and eighties In almost all cases that I know of, the version used was the Z80A, rated for 4 MHz, sometimes clocked a little slower in orde
- z80 - How do I Interface a PS 2 Keyboard without Modern Techniques . . .
It's a part of standard Z80 family chips and has two channels I used it for PS 2 keyboard and USB connection to my breadboard Z80 computer running at 2 4576 MHz Z84C40 can divide system clock by factor of 16, 32 or 64 thus I run my UART-USB bridge at 38,400 baud without use of 4-bit counter as system clock divider
|
|
|