From 416b1c10344bfe56bb7af2076f99514e33028978 Mon Sep 17 00:00:00 2001 From: AJR Date: Fri, 2 Jun 2017 19:50:29 -0400 Subject: A little more info on the YMZ chips (nw) --- src/devices/sound/ay8910.cpp | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/src/devices/sound/ay8910.cpp b/src/devices/sound/ay8910.cpp index ce513c89303..78847be413a 100644 --- a/src/devices/sound/ay8910.cpp +++ b/src/devices/sound/ay8910.cpp @@ -466,7 +466,13 @@ YM2203: 2 I/O ports The 'F' revision only appears during the first year of production. YM3439: limited info: CMOS version of YM2149? YMZ284: limited info: 0 I/O port, different clock divider + The chip selection logic is again simplified here: pin 1 is /WR, pin 2 is + /CS and pin 3 is A0. + D0-D7 are conveniently all on one side of the 16-pin package. + Pin 8 is /IC (initial clear), with an internal pullup. YMZ294: limited info: 0 I/O port + Pinout is identical to YMZ284 except for two additions: pin 8 selects + between 4MHz (H) and 6MHz (L), while pin 10 is /TEST. OKI M5255, Winbond WF19054, JFC 95101, File KC89C72, Toshiba T7766A : differences to be listed Decaps: -- cgit v1.2.3