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author Lord-Nightmare <Lord-Nightmare@users.noreply.github.com>2017-05-30 20:09:30 -0400
committer Lord-Nightmare <Lord-Nightmare@users.noreply.github.com>2017-05-30 20:09:30 -0400
commit2573117b74f2a510c80994e2798df35197f0e3e1 (patch)
tree747a19ada17e62cd5d9236f02c9314c3fb135bc1
parentb88e32514094aa0cab0897f37b47f72fd6fd20b7 (diff)
ay8910.cpp: add pinout, remove outdated comments from .h [Lord Nightmare]
-rw-r--r--src/devices/sound/ay8910.cpp92
-rw-r--r--src/devices/sound/ay8910.h15
2 files changed, 92 insertions, 15 deletions
diff --git a/src/devices/sound/ay8910.cpp b/src/devices/sound/ay8910.cpp
index b0eaabbcc69..bc1cf3bffef 100644
--- a/src/devices/sound/ay8910.cpp
+++ b/src/devices/sound/ay8910.cpp
@@ -251,6 +251,98 @@ has twice the steps, happening twice as fast.
***************************************************************************/
+/**
+AY-3-8910/8914/YM2149 (YM3439? others?)
+ _______ _______
+ _|* \__/ |_
+ [4] VSS (GND) -- |_|1 40|_| -- VCC (+5v)
+ _| |_
+ [5] NC |_|2 39|_| <- TEST 1 [1]
+ _| |_
+ ANALOG CHANNEL B <- |_|3 38|_| -> ANALOG CHANNEL C
+ _| |_
+ ANALOG CHANNEL A <- |_|4 37|_| <> DA0
+ _| |_
+ [5] NC |_|5 36|_| <> DA1
+ _| |_
+ IOB7 <> |_|6 35|_| <> DA2
+ _| |_
+ IOB6 <> |_|7 34|_| <> DA3
+ _| /---\ |_
+ IOB5 <> |_|8 \-/ | A 33|_| <> DA4
+ _| . . Y |_
+ IOB4 <> |_|9 |---| - S 32|_| <> DA5
+ _| ' ' 3 O |_
+ IOB3 <> |_|10 8 - U 31|_| <> DA6
+ _| 3 8 N |_
+ IOB2 <> |_|11 0 9 D 30|_| <> DA7
+ _| 8 1 |_
+ IOB1 <> |_|12 0 29|_| <- BC1
+ _| P |_
+ IOB0 <> |_|13 28|_| <- BC2
+ _| |_
+ IOA7 <> |_|14 27|_| <- BDIR
+ _| |_
+ IOA6 <> |_|15 26|_| <- TEST 2 [2]
+ _| |_
+ IOA5 <> |_|16 25|_| <- A8 [3]
+ _| |_
+ IOA4 <> |_|17 24|_| <- /A9 [3]
+ _| |_
+ IOA3 <> |_|18 23|_| <- /RESET
+ _| |_
+ IOA2 <> |_|19 22|_| == CLOCK
+ _| |_
+ IOA1 <> |_|20 21|_| <> IOA0
+ |__________________|
+
+[1] Based on the decap, TEST 1 affects the Envelope Generator and/or the
+ frequency divider somehow.
+[2] The TEST 2 input connects to the same selector as A8 and /A9 do on the 8910
+ and appears to act as just another active high enable like A8(pin 25) and
+ has an internal pull-up so if left NC the chip remains enabled.
+ On the 8914, it performs the same above function but additionally ?disables?
+ the DA0-7 bus if pulled low/active. This additional function was removed
+ on the 8910.
+ on YM2149 and YM3439 this pin is /SEL, if low, clock input is /2
+[3] It is possible for A8 and /A9 pins to be mask programmed to have different
+ active polarities. This might be true on the AY-3-8916/17 parts used on the
+ Intellivision ECS module? (not the Keyboard module?)
+[4] The bond wire for the VSS pin goes to the substrate frame, and then a
+ separate bond wire connects it to a pad between pins 21 and 22
+[5] These pins lack internal bond wires entirely.
+
+AY-3-8910/A: 2 I/O ports
+AY-3-8912/A: 1 I/O port; /A9 doesn't exist and is considered pulled low.
+AY-3-8913/A: 0 I/O port; BC2 pin doesn't exist and is considered pulled high.
+ Factory default for these three types when writing address data to them is:
+ /A9 must be low, A8 must be high, A7 thru A4 must be low.
+ A7 thru A4 enable state can be changed with a factory mask adjustment but
+ default was 0000 for the "common" part shipped.
+ The 'A' version of the 3 above have a re-laid out die, unclear if there are
+ any behavior changes vs the non-'A' version.
+AY-3-8914: same as 8910 except for different register mapping and two bit
+ envelope enable / volume field.
+ Factory default for these three types when writing address data to them is:
+ /A9 must be low, A8 must be high, A7 thru A4 must be low.
+ A7 thru A4 enable state can be changed with a factory mask adjustment but
+ are unknown for the one known part shipped, used in the Intellivision.
+AY8930: mostly backwards compatible with 8910, except like the AY-3-8913, the
+ BC2 pin is considered tied high/permanently '1'.
+ If the AY8930's extended mode is enabled, it gains higher resolution
+ frequency and volume control, separate volume per-channel, and the duty
+ cycle can be adjusted for the 3 channels. If the mode is not enabled, it
+ behaves exactly(?) like an AY-3-8910.
+YM2149: The envelope register has 5 bits of resolution internally, allowing for
+ smoother volume ramping, though the register for setting its direct value
+ remains 4 bits wide. The chip also has a selectable clock divider on pin 26
+ (/SEL), which was /TEST2 on the AY-3-8910. If low, the input clock is halved.
+YM3439: limited info: CMOS version of YM2149?
+YMZ284: limited info: 0 I/O port, different clock divider
+YMZ294: limited info: 0 I/O port
+OKI M5255, Winbond WF19054, JFC 95101, File KC89C72, Toshiba T7766A : differences to be listed
+*/
+
#include "emu.h"
#include "ay8910.h"
diff --git a/src/devices/sound/ay8910.h b/src/devices/sound/ay8910.h
index 44c04bf36b0..cf910729a69 100644
--- a/src/devices/sound/ay8910.h
+++ b/src/devices/sound/ay8910.h
@@ -5,21 +5,6 @@
#pragma once
-
-/*
-AY-3-8910A: 2 I/O ports
-AY-3-8912A: 1 I/O port
-AY-3-8913A: 0 I/O port
-AY-3-8914: same as 8910 except for different register mapping and two bit envelope enable / volume field
-AY8930: upper compatible with 8910.
-In extended mode, it has higher resolution and duty ratio setting
-YM2149: higher resolution, selectable clock divider
-YM3439: same as 2149
-YMZ284: 0 I/O port, different clock divider
-YMZ294: 0 I/O port
-OKI M5255, Winbond WF19054, JFC 95101, File KC89C72, Toshiba T7766A : differences to be listed
-*/
-
#define ALL_8910_CHANNELS -1
/* Internal resistance at Volume level 7. */