MEMORY PAGING IN LOW 16kB

[Black_Cat]

Only one 16kB ram page ?

Only all ROM & RAM page in CPU0(#0000-#3FFF) window

If 128kB memory is extended to 1-4MB why can't be extended also russian cache sram to more than 16 or 32kB ?

Also on new ZX clones ?

What ZX clones use this mode ?

This is an example of control in the window CPU0 for promising clones.

This don't need any hardware modification on FPGA clones and Garry Lancasted can ported RESIDOS to any ZX clone with low 16kB ram paging (but need also selectable writeprotect) and IDE ports.

Let Garry Lancasted porting RESIDOS for exUSSR standards. It's easier.

---------- Post added at 22:45 ---------- Previous post was at 22:38 ----------

Is impossible connect to this ZX-BUS connector any old ZX interface with external memory. This interfaces must be modified for work on russian clones. (can connect external memory only if in low 16kB is set rom - external interface set signal /RDROM to log.1).

Yes, ZXBUS it is not NemoBus

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[VELESOFT]

Let Garry Lancasted porting RESIDOS for exUSSR standards. It's easier.

TRDOS emulation in RESIDOS will in developlent. Actually can Residos access to FA16 partitions, open/create TAP files, work with sequential files, run SNA,Z80 snapshots, support save/load tasks (task manager in NMI menu), direct save/load files from ZX basic to FAT16. You can open one TAP file for loading and next TAP for saving. Big ram in low16kB enable switching between systems via one OUT xx,xx command (also in ZX basic). On Pentagon will theoretically possible acive RESIDOS via one OUT, open XXX.TRD file on fat 16 for sequential read and write this image file to real FDD. Or write sector copy of FDD to fat16 file. Transfer data between TRDOS and FAT16 is possible.

http://www.worldofspectrum.org/residos/

It's way as can work with TAP files and SNApshots on russian machines.

Yes, ZXBUS it is not NemoBus

On PENTAGON documantation is text " ZX-BUS (NEMO BUS) "
Pentagon 1024 use very compatible bus with original ZX Spectrum machines, only /ROMSC signal is on other pin (15).