Sanyo PHC-23J
This page was last modified 16:23, 25 October 2020 by Sd snatcher. Based on work by Sdsnatcher73 and Mars2000you and others.



The Sanyo PHC-23J, a.k.a Wavy23 is a MSX2 computer released by Sanyo, and aimed at the Japanese market. It is the sequel to the PHC-23. The difference seems to be that the PHC-23J has a JIS compliant keyboard, unlike the PHC-23. Three revisions of the Wavy23 were produced.

Product Released Keyboard Color Sanyo logo MSX Engine Battery
Sanyo PHC-23 1986 JP50on Grey old style Yamaha S3527 Internal re-chargable
Sanyo PHC-23J 1987 JIS Grey old style Yamaha S3527 Internal re-chargable
Sanyo PHC-23J(B) 1987 JIS Blue new style Yamaha S1985 two AA batteries

The PHC-23J has been localised for the Russian market with more RAM (see MPC-2300).

Brand Sanyo
Type PHC-23J / PHC-23J(B)
Year 1987
Region Japan
Original price ¥32,800
RAM 64kB (in slot 3-2)
VRAM 128kB
Media MSX cartridges
Video Yamaha V9938
Audio PSG (YM2149 integrated in MSX-Engine S1985 or S3527)
Chipset Yamaha S1985 or Yamaha S3527
Keyboard layout JIS
Emulation ROMs dumped and emulated for the PHC-23J and PHC-23J(B).


Sanyo PHC-23J
Sanyo PHC-23J right side
Sanyo PHC-23J(B)
Sanyo PHC-23J(B) with manuals
Sanyo PHC-23J(B) model sticker
Sanyo PHC-23J(B) PCB
Sanyo PHC-23J bottom
Sanyo PHC-23J(B) bottom
Sanyo PHC-23J box
Sanyo PHC-23J back


The PHC-23J is a MSX2 with a Z80A from NEC (D780C-1) and an MSX-Engine S1985 or S3527 from Yamaha.

Slot Map

Slot 0 Slot 1 Slot 2 Slot 3-0 Slot 3-1 Slot 3-2 Slot 3-3
Page C000h~FFFFh Cartridge
Slot 1
Slot 2
Page 8000h~BFFFh
Page 4000h~7FFFh Main-ROM
Page 0000h~3FFFh Sub-ROM