Differences

This shows you the differences between two versions of the page.

--- vendor:yamaha [2017/04/25 17:16] – lost one, fixed lord_nightmare
+++ vendor:yamaha [2025/08/04 21:23] (current) – external edit 127.0.0.1
@@ Line 4: / Line 4: @@
 According to Tiido and others, Yamaha is a fabless vendor, and has other chip manufacturers do all of their silicon fabrication and packaging. Examples being Fujitsu, Sharp, Hitachi, ROHM.
+====== Getting Started ======
+[[vendor:yamaha:FM|FM Theory]]
+[[vendor:yamaha:OPL2|OPL2]]
 ====== Datecode ======
@@ Line 9: / Line 15: @@
   Yamaha Datecode/Markings:
 -1989 'old style': (may have been used very briefly in 1990)
-  yM ww Ll r
+  ym dd Ll r
+  m = month (1-9 = Jan-Sep, X=oct, Y=nov, Z=dec)
+  dd = day within month
+  L might be a manufacturer code, but could also be the msb of the lot code?
 + 'new style':
   Yyww MLlr
   Y = year most significant (9 or 0 or 1 for 199x or 200x or 201x)
   y = year least significant (2 = 1982, 3 = 1983 ... etc ... 9 = 1989) (0 = 1990?)
+  ww = week within year
   M = Manufacturer code, see table below; old style and new style chips have different tables
   Ll = lot code/batch code?
-  ww = week within year
   r = die revision
 ====== Fabs ======
-  'old style' markings:
-=
-= Sharp?
-=
-(= L) = Hitachi 2
-= Sharp [probably = I below]
-= Hitachi
-=
-= Hitachi or ROHM (NDIP)?
-  X =
-  Y = Hitachi?
-  Z = Fujitsu
   'new style':
-  A = Sharp 2
+  A = Yamaha (Kagoshima)
   C = Hitachi 2a
   D =
@@ Line 43: / Line 40: @@
   G = Hitachi 1a?
   H = Sharp 1
-  I = Sharp [probably = 5 above]
+  I (= 5) = Sharp (95% certain)
   L (= 4) = Hitachi 2
   O =
-  Z = Fujitsu [This is interesting, possibly a printing error which should have been F but they printed a Z instead?]
+  Z = Fujitsu 2
 ====== Chips ======