KM23V4000D(E)TY/KM23S4000D(E)TY 4M-Bit (512Kx8) CM.
KM23V4000D - (KM23x4000xTY) 4M-Bit CMOS Mask ROM
KM23V4000DTY - (KM23x4000xTY) 4M-Bit CMOS Mask ROM