SANYO WAVY 70FD MSX2+ RAM Expansion

By JAPANRETRO

Rookie (24)

09-03-2007, 13:55

Hi !
Someone knows how to expand 64kb memory of my Sanyo onboard?
There is a tutorial on the net?
Regards.
Davide.

By Repair-Bas

Paragon (1176)

09-03-2007, 16:25

very simple

put two Ram IC's in the spare-places and 2 condensators

By Ivan

Ascended (9371)

09-03-2007, 20:03

Not true, I expanded a Wavy70 to 128kB long time ago -putting 64kB into the free socket- and you have to solder two memory pins between the two RAM chips and change a jumper.

By Ivan

Ascended (9371)

09-03-2007, 20:11

Read!: http://www.msx.org/forumtopic3929.html

:) :) :)

By dhau

Paragon (1570)

17-03-2007, 05:40

I did the 512K upgrade on Wavy 35J. I don't think 70FD is a lot different. I had to remove 2x4464 dram chips and wire four 44256 chips on a small separate pcb, then use wires from IDE cable to connect all signals from original 4464 sockets and two more signals from MSX engine chip. Alexandro, MSX user from Brazil, made similar upgrade a year after me and he even documented all the process. If I'll find the link to his instruction, I'll post it here.

By dhau

Paragon (1570)

17-03-2007, 05:44

As I promised: Tabajara Labs Wavy 70FD2 512K

Just a consideration: I used shorter wires and had decoupling capacitors on top of each dram chip.

By novi_skt

Supporter (7)

14-04-2007, 12:17

hi, im a spanish user.
in a two wheeks i have a wavy msx 2+, and i like upgrade to 512k.
when the msx are in my hands i'm try make a little pcb for the esasy upgrade,
but im not read portugues, are more info in english??

sorry for my english!!!