8bit Projects For Everyone


Find   for  

Samtrum

Three development versions of Samtrum are planned.

Samtrum 1

Will be simplest as possible. Only 4MB RAM and socket for Z80CPU, at 6MHz and 3.5MHz, perhaps 8MHz if it will work. Perhaps a YABUS slot. Samtrum 1 will work as:

1. 4MB RAM extension (Sam has 4.5MB).

2. ZX128 hardware emulator (when the second Z80CPU is inserted and enabled). 4MB RAM is available.

Samtrum 2

Will have buffers and extra switching logic, so more modes will be available:

3. Both the internal and the extra Z80 will be able to work in the same time. The internal one operates on internal 512kB RAM and internal interfaces (keyboard, FDD, Atom), while the external one on 4MB RAM and external interfaces (Sambus, YABUS). To exchange data between them, other mode must be selected (and one CPU disabled).

4. 512kB RAM of the 4MB RAM duplicates the internal RAM and only external CPU works. The internal RAM is only written by CPU (delayed if necessary for faster clock - up to 21MHz due to 60ns DRAM access time). Sam has 4MB RAM, but can work with very fast CPU.

Samtrum 3

Will have and support my new bus, that allows to use CPU cards, graphics cards, DMA cards and configuration cards. New modes:

5. Without CPU card, Sam can work with graphics cards and some DMA cards.

6. With CPU card (I mean here eZ80) Sam hardware is used as graphics and I/O card. Samtrum 3 offers default "Sam compatibility" configuration, but with an extra configuration card its structure can be converted to almost any hardware compatibility (e.g. ZS Scorpion, ZX Spectrum +3).

Purposes

  • Using Sam with 4.5MB RAM
  • Hardware emulation of ZX Spectrum 128kB.
  • Hardware emulation of Pentagon 512kB.
  • Using Z80 up to 16MHz.
  • Using Z88 software.

Properties

  • 4MB 60ns DRAM
  • Z80 with own programmable clock and WAIT control.
  • YABUS slots.
  • Up to 512kB Flash EPROM (not sure).
  • Memory switched using #D0..#D3 ports, as in Z88.
  • Alternate memory switchind in ports #80, #81 (Sam).
  • Alternate memory switching with port #7FFD (ZX128).
  • ZX128 emulation supported in ZXVGS.


Tell other people:

Links to other pages



See also

Sam Coupé
The Sam Coupé computer by MGT.
DRAM
Dinamic Random Access Memory (DRAM). Memory with multiplexed address lines.
4MB RAM upgrade : ZX Spectrum
ZX Spectrum memory upgrade - 4MB RAM (DRAM).

E-mail:

Password:



Forgot password?

Register?
Apple
HDD
Atari
IDE KMK/J¯
MyIDE
SIO2IDE
Commodore
IECATA
CPC
CPCISA
Hacker
PC
IDE
LPT
Sam Coupé
Atom
FDD
RTC
Samtrum
YABUS.SAM
YAMOD
ATBUS
AYLPT
EPROG
FDC765A
IDE8255
KJOY
ZXINPUT
Timex
BEU
Cartridge
FD-68
Larken
ZX81
ZX96
ZX1541
ZX Spectrum
AC-DOS
Interface 1
Interface 1 Bis
Interface 2
GeneralSound
Macface
MB-02
NMI
Packet Radio
PB-3
PL3MEM
Plus D
POLBASIC
Printer
Split
Timex M-397
CA80
YABUS.ZX
YABUS.ZXISA
YABUS.ZXMEM

If you see error on this page, describe here:

© 2009-12-28 21:50 Jarek Adamski, http://8bit.yarek.pl