MSX1 Memory Mapper
Looks Ok,
No it doesn't. If you're gonna use RAM chip(s) with SRAM/EPROM-like pinout, then at least use a proper SRAM, not a pseudo-SRAM that has NO practical advantage.
but if you want to use that as the main RAM (no linear 32K or 64K) you'll need some mechanism to initialize the pages. MSX2 BIOS does that, but MSX1 BIOS does not. If all pages remain 0 at boot, MSX will eventually crash.
No it won't. An MSX will still boot even with the same 16K RAM block selected in all pages. From there on, you can manually initialize the mapper with a few BASIC commands, and reset the MSX. Granted, that's a hassle. But it does work that way.
If you don't want that hassle, then for MSX1 you're looking at modified system ROM or a CPLD-based mapper (@blackmsx: have you checked out my 512K one? 
Quite diy-able).
Also, that one misses so called back annotation feature. I'm not sure how important it is anyway.
Not too important. Especially not for well-written / standards-compliant software. But there's a lot of crap out there, and people still want to run that... 
That's why having back annotation is preferred.
If you only need 128KB mapped RAM you can buid a simple Gouget mapper with only 3 discret components.
Like RetroTechie said you should manually initialize the mapper but I'm not sure you must restart the MSX.
No it won't. An MSX will still boot even with the same 16K RAM block selected in all pages. From there on, you can manually initialize the mapper with a few BASIC commands, and reset the MSX. Granted, that's a hassle. But it does work that way.
If you don't want that hassle, then for MSX1 you're looking at modified system ROM or a CPLD-based mapper (@blackmsx: have you checked out my 512K one? Quite diy-able).
I haven check yours, could you point me to it?
How do you initialize the mapper from basic? (sorry guys, Im new in MSX)
256KB DRAM memory mapper installed on VG8020/00
I also modded the BIOS to auto init the mapper. I use a modded MEGASCSI with it (DOS2 patched to skip MSX2 detection works fine with this computer).
Original and new RAM chips before install.