Programmer's Guide to Yamaha YMF 262/OPL3 FM Music Synthesizer
Version 1.00 Nov-24-1994
Written by Vladimir Arnost, QA-Software
Internet: xarnos00@dcse.fee.vutbr.cz
This manual can be distributed freely if not modified.
DISCLAIMER: I assume no responsibility for any damages arising out of
---------- use or inability to use this text. No warranty is provided
about correctness of any information in this file. You are
on your own.
INTRODUCTION
------------
The chip I am going to describe is getting more and more common, but
programming information is still scarce, so I have decided to fill in this
gap. All information contained in this file is a result of my experience in
Adlib programming, research (read: reverse engineering) and finally of my
effort to write down everything necessary to understand and use this piece
of hardware. No official sources (i.e. development kits, books about this
topic, etc.) were available to me except:
Adlib Programming Guide - by Tero T"tt", and
The PC Games Programmers Encyclopedia V1.0
The information below is a combination of known features of Adlib (alias
Yamaha YM 3812/OPL2) and my own uncountable experiments and failures, which
brought out a lot of important details you have to know about the chip.
As far as I know, there are four major sound cards based on OPL3 chip:
* Sound Blaster Pro II (not Sound Blaster Pro I)
* Sound Blaster 16
* Adlib Gold
* Pro Audio Spectrum Plus/16
I currently have a Sound Blaster Pro II-compatible card only, so all the
programming info I provide will be based on this card. (The other cards
are quite similar, however. They are just wired at different I/O-port
addresses.)
Note: I assume some knowledge of FM music programming (mainly Adlib FM
synthesizer) in this manual. If you are new to this topic I recommend
you try Adlib first before going higher. Anyway, OPL3 is a direct
descendant of OPL2 (what a surprise), so most features of OPL2 are
also present on OPL3.
DESCRIPTION OF THE SYNTHESIZER
------------------------------
My card's user manual says: "[this card contains] ... a stereo music
FM synthesizer with 20 channels consisting of four (4) operators each ... "
I thought: "Wow -- that's together eighty operators. This must be a GOOD
sound-card." I was wrong. Just another advertising lie.
So let's clear some facts. First, OPL3 has only thirty-six (36) operators
which can be combined in several ways:
* 18 FM channels (36 operators), or
* 15 FM channels (30 ops) and 5 percussion instruments (6 ops), giving
us 20 channels altogether, or
* up to 6 four-operator FM channels (max 24 ops), the rest again being
divided into two-operator FM channels and drums.
From the table above you can see that not all channels can be used in four-
operator (4-OP) mode -- only a part of the synthesizer is really capable of
making 4-OP sounds -- the rest uses traditional two-operator (2-OP) mode.
Second, the manual states this card is capable of "stereo" music. Yes, the
quotes are necessary, because the stereo capabilities are very limited.
You are given ability to control output going to left or right channel by
turning it on and off. That's all. So the sound can flow from very left side,
center and very right side. No sound panning, no special stereo effects. :-(
Well, flaming apart, back to the main topic.
The OPL3 chip is capable of making sounds in several ways:
1. Two-operator Additive Synthesis
Output of both operators is simply added. It is the simplest way to
make any sound, and it works on both OPL2 and OPL3. The diagram
should make it clear.
旼컴컴컴컴컴커
� �
� Operator 1 쳐컴컴컴커
� � �
읕컴컴컴컴컴켸 �
쳐컴컴컴�> Output
旼컴컴컴컴컴커 �
� � �
� Operator 2 쳐컴컴컴켸
� �
읕컴컴컴컴컴켸
2. Two-operator Frequency Modulation (FM) Synthesis
Output from the first operator (Modulator) is sent to the input of the
second one (Carrier) and is used to modulate (alter) frequency of the
second operator. Only the second operator produces sound. Most of
interesting sounds are made this way. This also works on OPL2.
Hope the picture helps.
旼컴컴컴컴컴커 旼컴컴컴컴컴커
� � � �
� Operator 1 쳐컴컴컴�>� Operator 2 쳐컴컴컴�> Output
�(Modulator) � � (Carrier) �
읕컴컴컴컴컴켸 읕컴컴컴컴컴켸
3. Four-operator "Mess" Modulation Synthesis
All of OPL3's 4-OP configurations are combinations of the above two modes
of synthesis. OPL3 combines these two modes in four ways. I have no words
to describe these four ways. Only the pictures can show their principle.
a) FM-FM Mode
旼컴컴컴� 旼컴컴컴� 旼컴컴컴� 旼컴컴컴�
� � � � � � � �
� Op. 1 쳐컴컴>� Op. 2 쳐컴컴>� Op. 3 쳐컴컴>� Op. 4 쳐컴컴> Output
� � � � � � � �
읕컴컴컴� 읕컴컴컴� 읕컴컴컴� 읕컴컴컴�
b) AM-FM Mode
旼컴컴컴�
� �
� Op. 1 쳐컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
� � �
읕컴컴컴� �
�
旼컴컴컴� 旼컴컴컴� 旼컴컴컴� �
� � � � � � �
� Op. 2 쳐컴컴>� Op. 3 쳐컴컴>� Op. 4 쳐컴컴좔컴컴> Output
� � � � � �
읕컴컴컴� 읕컴컴컴� 읕컴컴컴�
c) FM-AM Mode
旼컴컴컴� 旼컴컴컴�
� � � �
� Op. 1 쳐컴컴>� Op. 2 쳐컴컴�
� � � � �
읕컴컴컴� 읕컴컴컴� �
쳐컴컴> Output
旼컴컴컴� 旼컴컴컴� �
� � � � �
� Op. 3 쳐컴컴>� Op. 4 쳐컴컴�
� � � �
읕컴컴컴� 읕컴컴컴�
d) AM-AM Mode
旼컴컴컴�
� �
� Op. 1 쳐컴컴컴컴컴컴컴컴컴커
� � �
읕컴컴컴� �
�
旼컴컴컴� 旼컴컴컴� �
� � � � �
� Op. 2 쳐컴컴>� Op. 3 쳐컴컴탠컴컴> Output
� � � � �
읕컴컴컴� 읕컴컴컴� �
�
旼컴컴컴� �
� � �
� Op. 4 쳐컴컴컴컴컴컴컴컴컴켸
� �
읕컴컴컴�
Nice, aren't they?
The only way I think this can be written is a math formula.
Symbol + (plus) means additive synthesis, and * (asterisk) means
frequency modulation (Op1 * Op2 means operator 1 modulates operator 2,
not vice versa). Here they are:
a) FM-FM Mode: (Op1 * Op2 * Op3 * Op4) 컴컴> Output
b) AM-FM Mode: Op1 + (Op2 * Op3 * Op4) 컴�> Output
c) FM-AM Mode: (Op1 * Op2) + (Op3 * Op4) 컴> Output
d) AM-AM Mode: Op1 + (Op2 * Op3) + Op4 컴�> Output
4. Percussion Mode
In this mode 6 operators are used to produce five different percussion
instruments:
* Bass Drum (2 operators)
* Snare Drum (1 operator)
* Tom-Tom (1 operator)
* Cymbal (1 operator)
* Hi-Hat (1 operator)
Because these instruments occupy only three melodic channels, only
Bass Drum, Snare Drum and Tom-Tom frequencies can be set. Cymbal and
Hi-Hat frequencies are fixed.
This mode is identical with that of OPL2. For more details see ADLIB.DOC.
PROGRAMMING THE SYNTHESIZER
---------------------------
OPL3 may be found at the following addresses:
Sound Blaster Pro II 220h or 240h (selectable), also 388h
Adlib Gold 388h
Pro Audio Spectrum Plus/16 ? (if you have a PAS you should know it)
The base address of the synthesizer will be called "base".
The chip occupies four I/O addresses:
base+0 Primary index register (write), Status register (read)
base+1 Primary data register (write-only)
base+2 Secondary index register (write)
base+3 Secondary data register (write-only)
The index registers are used to select internal registers and data registers
are used to write to them. Status register returns the state of two timers
built in the chip.
OPL3 contains two sets of registers. The Primary set maps to channels 0-8
(operators 0-17) and the secondary maps to channels 9-17 (operators 18-35).
The reason for this is simple: all these registers wouldn't fit into single
register set.
Unlike Adlib (OPL2), OPL3 doesn't need delay between register writes.
With OPL2 you had to wait 3.3 �s after index register write and another
23 �s after data register write. On the contrary OPL3 doesn't need
(almost) any delay after index register write and only 0.28 �s after data
register write. This means you can neglect the delays and slightly speed up
your music driver. But using reasonable delays will certainly do no harm.
The data registers can't be read (they are write-only) on both OPL2 and OPL3.
REGISTER MAP
------------
The registers are grouped in the same manner as in the OPL2 chip. Programs
using both OPL2 and OPL3 chips may use the same code provided that their
direct I/O interface is well written. The only thing you have to change is
operator-to-register mapping, which must accomodate the fact that registers
are spread between two register sets.
(The register map is nearly the same so I dared to copy it from ADLIB.DOC.)
Status Register (base+0):
旼컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
� D7 D6 D5 D4 D3 D2 D1 D0 �
쳐컴컴컴컵컴컴컴컴탠컴컴컴컵컴컴컴컴좔컴컴컴컨컴컴컴컴좔컴컴컴컨컴컴컴컴�
쿔RQFlag � T1Flag � T2Flag � �
읕컴컴컴컨컴컴컴컴좔컴컴컴컨컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
Data Registers (base+1, base+3):
旼컴컴쩡컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
� REG � D7 D6 D5 D4 D3 D2 D1 D0 �
쳐컴컴탠컴컴컴컨컴컴컴컴탠컴컴컴컵컴컴컴컴좔컴컴컴컨컴컴컴컴좔컴컴컴컨컴컴컴컴�
� 01 � 쿥SEnable� Test Register �
쳐컴컴탠컴컴컴컴컴컴컴컴좔컴컴컴컨컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
� 02 � Timer 1 Count (80 �sec resolution) �
쳐컴컴탠컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
� 03 � Timer 2 Count (320 �sec resolution) �
쳐컴컴탠컴컴컴컫컴컴컴컴쩡컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴쩡컴컴컴컫컴컴컴컴�
� 04* 쿔RQReset� T1Mask � T2Mask � 쿟2 Start쿟1 Start�
쳐컴컴탠컴컴컴컨컴컴컴컴탠컴컴컴컵컴컴컴컴쩡컴컴컴컫컴컴컴컴탠컴컴컴컵컴컴컴컴�
� 04**� �4-OP B-E�4-OP A-D�4-OP 9-C�4-OP 2-5�4-OP 1-4�4-OP 0-3�
쳐컴컴탠컴컴컴컴컴컴컴컴좔컴컴컴컨컴컴컴컴좔컴컴컴컨컴컴컴컴좔컴컴컴컵컴컴컴컴�
� 05**� � OPL3 �
쳐컴컴탠컴컴컴컫컴컴컴컴쩡컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컨컴컴컴컴�
� 08 � CSW 쿙OTE-SEL� �
쳐컴컴탠컴컴컴컵컴컴컴컴탠컴컴컴컫컴컴컴컴쩡컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
�20-35쿟remolo 쿣ibrato 쿞ustain � KSR � Frequency Multiplication Factor �
쳐컴컴탠컴컴컴컨컴컴컴컴탠컴컴컴컨컴컴컴컴좔컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
�40-55� Key Scale Level � Output Level �
쳐컴컴탠컴컴컴컴컴컴컴컴좔컴컴컴컴컴컴컴컴쩡컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
�60-75� Attack Rate � Decay Rate �
쳐컴컴탠컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴탠컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
�80-95� Sustain Level � Release Rate �
쳐컴컴탠컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴좔컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
쿌0-A8� Frequency Number ( Lower 8 bits ) �
쳐컴컴탠컴컴컴컴컴컴컴컴쩡컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴쩡컴컴컴컴컴컴컴컴�
쿍0-B8� � KEY-ON � Block Number � F-Num (hi bits) �
쳐컴컴탠컴컴컴컫컴컴컴컴탠컴컴컴컵컴컴컴컴쩡컴컴컴컫컴컴컴컴탠컴컴컴컫컴컴컴컴�
� BD 쿟rem Dep쿣ibr Dep쿛ercMode� BD On � SD On � TT On � CY On � HH On �
쳐컴컴탠컴컴컴컨컴컴컴컴탠컴컴컴컵컴컴컴컴탠컴컴컴컨컴컴컴컴좔컴컴컴컵컴컴컴컴�
쿎0-C8� � Right � Left 쿑eedBack Modulation Factor쿞ynthTyp�
쳐컴컴탠컴컴컴컴컴컴컴컴좔컴컴컴컨컴컴컴컴좔컴컴컴컫컴컴컴컴컴컴컴컴컨컴컴컴컴�
쿐0-F5� � Waveform Select �
읕컴컴좔컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컨컴컴컴컴컴컴컴컴컴컴컴컴컴�
Notes:
* This applies only to port base+1
** This applies only to port base+3
For register bases A0, B0 and C0 there is one register per output channel.
The primary register set holds the first nine channels (0-8) and the secondary
holds last nine channels (9-17).
For bases 20, 40, 60, 80 and E0 there are two registers per channel. Each
register maps to one operator. Unfortunately the operator's register numbers
are not continuous. The following table shows which operator maps to which
register set and offset (in hex).
旼컴컴컴컴컴컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴�
� Op. Set/Offset � Op. Set/Offset �
쳐컴컴컴컴컴컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴�
� 0 0/00 � 18 1/00 �
� 1 0/01 � 19 1/01 �
� 2 0/02 � 20 1/02 �
� 3 0/03 � 21 1/03 �
� 4 0/04 � 22 1/04 �
� 5 0/05 � 23 1/05 �
� 6 0/08 � 24 1/08 �
� 7 0/09 � 25 1/09 �
� 8 0/0A � 26 1/0A �
� 9 0/0B � 27 1/0B �
� 10 0/0C � 28 1/0C �
� 11 0/0D � 29 1/0D �
� 12 0/10 � 30 1/10 �
� 13 0/11 � 31 1/11 �
� 14 0/12 � 32 1/12 �
� 15 0/13 � 33 1/13 �
� 16 0/14 � 34 1/14 �
� 17 0/15 � 35 1/15 �
읕컴컴컴컴컴컴컴컴컴컨컴컴컴컴컴컴컴컴컴컴�
The following tables summarize which operators form a channel in various
modes:
1. Two-operator Melodic Mode
旼컴컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
� Channel � 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 �
쳐컴컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
� Operator 1 � 0 1 2 6 7 8 12 13 14 18 19 20 24 25 26 30 31 32 �
� Operator 2 � 3 4 5 9 10 11 15 16 17 21 22 23 27 28 29 33 34 35 �
읕컴컴컴컴컴컨컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
2. Two-operator Melodic and Percussion Mode
旼컴컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
� Channel � 0 1 2 3 4 5 BD SD TT CY HH 9 10 11 12 13 14 15 16 17 �
쳐컴컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
� Operator 1 � 0 1 2 6 7 8 12 16 14 17 13 18 19 20 24 25 26 30 31 32 �
� Operator 2 � 3 4 5 9 10 11 15 21 22 23 27 28 29 33 34 35 �
읕컴컴컴컴컴컨컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
3. Four-operator Melodic Mode
旼컴컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴커
� Channel � 0 1 2 6 7 8 9 10 11 15 16 17 �
쳐컴컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴캑
� Operator 1 � 0 1 2 12 13 14 18 19 20 30 31 32 �
� Operator 2 � 3 4 5 15 16 17 21 22 23 33 34 35 �
� Operator 3 � 6 7 8 24 25 26 �
� Operator 4 � 9 10 11 27 28 29 �
읕컴컴컴컴컴컨컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴켸
Channels 3, 4, 5 and 12, 13, 14 can't be used separately because their
operators became part of channels 0, 1, 2 and 9, 10, 11 respectively.
For instance a four-operator channel 1 consists of two two-operator
channels number 1 and 4. (The second 2-OP channel number is always the
first 2-OP channel number plus three.)
OPL3 allows you to enable/disable 4-OP mode separately for any of
channels 0, 1, 2, 9, 10 and 11 (see register 104h in the reference below).
This means for instance when you switch only channel 2 into 4-OP mode,
channels number 0, 1, 3, 4, 6, 7, 8, 9, etc. will be still independent
2-OP channels.
Channels 6, 7, 8 and 15, 16, 17 are always two-operator ones. They can't
be grouped to form four-operator channels.
4. Four-operator Melodic and Percussion Mode
旼컴컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
� Channel � 0 1 2 BD SD TT CY HH 9 10 11 15 16 17 �
쳐컴컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
� Operator 1 � 0 1 2 12 16 14 17 13 18 19 20 30 31 32 �
� Operator 2 � 3 4 5 15 21 22 23 33 34 35 �
� Operator 3 � 6 7 8 24 25 26 �
� Operator 4 � 9 10 11 27 28 29 �
읕컴컴컴컴컴컨컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
Examples:
* Two-operator channel #14 consists of operators 26 and 29 which occupy
these registers (all are in the secondary register set):
12A - Operator 1 - Tremolo/Vibrato/Sustain/KSR/Multiplication
12D - Operator 2 - Tremolo/Vibrato/Sustain/KSR/Multiplication
14A - Operator 1 - Key Scale Level/Output Level
14D - Operator 2 - Key Scale Level/Output Level
16A - Operator 1 - Attack Rate/Decay Rate
16D - Operator 2 - Attack Rate/Decay Rate
18A - Operator 1 - Sustain Level/Release Rate
18D - Operator 2 - Sustain Level/Release Rate
1A5 - Frequency Number (low)
1B5 - Key On/Block Number/Frequency Number (high)
1C5 - FeedBack/Synthesis Type
1EA - Operator 1 - Waveform Select
1ED - Operator 2 - Waveform Select
* Four-operator channel #1 consists of operators 1, 4, 7 and 10. All
registers except register 104h are in the primary set:
104 - bit 1 = 1 - Enable Four-Operator Synthesis in channel #1
21 - Operator 1 - Tremolo/Vibrato/Sustain/KSR/Multiplication
24 - Operator 2 - Tremolo/Vibrato/Sustain/KSR/Multiplication
29 - Operator 3 - Tremolo/Vibrato/Sustain/KSR/Multiplication
2C - Operator 4 - Tremolo/Vibrato/Sustain/KSR/Multiplication
41 - Operator 1 - Key Scale Level/Output Level
44 - Operator 2 - Key Scale Level/Output Level
49 - Operator 3 - Key Scale Level/Output Level
4C - Operator 4 - Key Scale Level/Output Level
61 - Operator 1 - Attack Rate/Decay Rate
64 - Operator 2 - Attack Rate/Decay Rate
69 - Operator 3 - Attack Rate/Decay Rate
6C - Operator 4 - Attack Rate/Decay Rate
81 - Operator 1 - Sustain Level/Release Rate
84 - Operator 2 - Sustain Level/Release Rate
89 - Operator 3 - Sustain Level/Release Rate
8C - Operator 4 - Sustain Level/Release Rate
A1 - Frequency Number (low)
A4 - Unused
B1 - Key On/Block Number/Frequency Number (high)
B4 - Unused
C1 - FeedBack/Synthesis Type (part 1)
C4 - Synthesis Type (part 2)
E1 - Operator 1 - Waveform Select
E4 - Operator 2 - Waveform Select
E9 - Operator 3 - Waveform Select
EC - Operator 4 - Waveform Select
NOTE: If a register number is greater than 100h, then it belongs into the
secondary register set. (I use this numbering to emphasize the fact
that the particular register MUST be written to the secondary set.)
See Appendix A.
OPL3 REGISTER REFERENCE
-----------------------
Because the registers of OPL3 are almost the same as of OPL2, I have copied
their descriptions from file ADLIB.DOC.
* Status Register:
靈7컫�6컫�5컫�4컫�3컫�2컫�1컫�0캠
튘RQ쿟1 쿟2 � Not used �
聃컴좔컴좔컴좔컴좔컴좔컴좔컴좔컴1/2
bit 7: IRQ Flag. Set whenever any timer has elapsed.
bit 6: Timer 1 Flag. Set every time the preset time in Timer 1 has elapsed.
bit 5: Timer 2 Flag. Set every time the preset time in Timer 2 has elapsed.
Timer interrupts are not wired to any IRQ (why??). The timers can be used
to detect the OPL2/OPL3 chip (see Appendix B).
* Data Registers:
01: Test Register / Waveform Select Enable:
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� 쿥SE� Test Register �
聃컴좔컴좔컴좔컴좔컴좔컴좔컴좔컴1/2
bit 5: Waveform Select Enable. If clear, all channels will use normal
sine wave. If set, register E0-F5 (Waveform Select) contents
will be used.
bits 0-4: Test Register. Must be reset to zero before any operation.
02: Timer 1 Count:
Upward 8 bit counter with a resolution of 80 �sec. If an overflow occurs,
the status register bit is set, and the preset value is loaded into the
timer again.
03: Timer 2 Count:
Same as Timer 1, but with a resolution of 320 �sec.
004 (port: base+1): IRQ-Reset / Mask / Start:
靈7컫�6컫�5컫�4컫�3컫�2컫�1컫�0캠
튣st쿟1M쿟2M� 쿟2S쿟1S�
聃컴좔컴좔컴좔컴좔컴좔컴좔컴좔컴1/2
bit 7: IRQ-Reset. Resets timer and IRQ flags in status register.
All other bits are ignored when this bit is set.
bit 6: Timer 1 Mask. If 1, status register is not affected in overflow.
bit 5: Timer 2 Mask. Same as above.
bit 1: Timer 2 Start. Timer on/off.
bit 0: Timer 1 Start. Same as above.
104 (port: base+3): Four-Operator Enable:
靈7컫�6컫�5컫�4컫�3컫�2컫�1컫�0캠
� 쿎hB쿎hA쿎h9쿎h2쿎h1쿎h0�
聃컴좔컴좔컴좔컴좔컴좔컴좔컴좔컴1/2
bit 5: Enable four-operator synthesis for channel pair 11 - 14 (decimal).
bit 4: Same as above for channel pair 10 - 13.
bit 3: Same as above for channel pair 9 - 12.
bit 2: Same as above for channel pair 2 - 5.
bit 1: Same as above for channel pair 1 - 4.
bit 0: Same as above for channel pair 0 - 3.
If reset to zero, OPL3 can produce 18 two-operator sounds at a time.
If nonzero, OPL3 produces four-operator sound in appropriate channel pair.
105 (port: base+3): OPL3 Mode Enable:
靈7컫�6컫�5컫�4컫�3컫�2컫�1컫�0캠
� 쿚PL�
聃컴좔컴좔컴좔컴좔컴좔컴좔컴좔컴1/2
bit 0: OPL3 Mode Enable. When set, OPL3 extensions (36 operators, 4-OP
synthesis, 8 waveforms, stereo output) can be used. When reset,
the chip behaves as an ordinary OPL2. This bit is zero by default
for compatibility with OPL2.
08: CSW / NOTE-SEL:
靈7컫�6컫�5컫�4컫�3컫�2컫�1컫�0캠
튏SW쿙-S� �
聃컴좔컴좔컴좔컴좔컴좔컴좔컴좔컴1/2
bit 7: Composite sine wave mode on/off. All KEY-ON bits must be clear
in order to use this mode. The card is unable to create any other
sound when in CSW mode. (Unfortunately, I have no info how to
use this mode :-< ).
bit 6: NOTE-SEL. Controls the split point of the keyboard. When 0, the
keyboard split is the second bit from the bit 8 of the F-Number.
When 1, the MSb of the F-Number is used. (???)
20-35: Tremolo / Vibrato / Sustain / KSR / Frequency Multiplication Factor:
靈7컫�6컫�5컫�4컫�3컫�2컫�1컫�0캠
튦re쿣ib쿞us쿖SR� Multiplication�
聃컴좔컴좔컴좔컴좔컴좔컴좔컴좔컴1/2
bit 7: Tremolo (Amplitude vibrato) on/off.
bit 6: Frequency vibrato on/off.
bit 5: Sound Sustaining. When 1, operator's output level will be held at
its sustain level until a KEY-OFF is done.
bit 4: Envelope scaling (KSR) on/off. When 1, higher notes are shorter
than lower notes.
bits 0-3: Frequency Multiplication Factor (MULTI). Operator's frequency
is set to (see registers A0, B0) F-Number * Factor.
旼컴컴컴쩡컴컴컴커
� MULTI � Factor �
쳐컴컴컴탠컴컴컴캑
� 0 � � �
� 1 � 1 �
� 2 � 2 �
� 3 � 3 �
� 4 � 4 �
� 5 � 5 �
� 6 � 6 �
� 7 � 7 �
� 8 � 8 �
� 9 � 9 �
� 10 � 10 �
� 11 � 10 �
� 12 � 12 �
� 13 � 12 �
� 14 � 15 �
� 15 � 15 �
읕컴컴컴좔컴컴컴켸
40-55: Key Scale Level / Output Level:
靈7컫�6컫�5컫�4컫�3컫�2컫�1컫�0캠
� KSL � Output Level �
聃컴좔컴좔컴좔컴좔컴좔컴좔컴좔컴1/2
bits 6-7: Key Scale Level. Attenuates output level towards higher pitch:
旼컴컴쩡컴컴컴컴컴컴�
� KSL � Attenuation �
쳐컴컴탠컴컴컴컴컴컴�
� 0 � - �
� 1 � 1.5 dB/oct �
� 2 � 3.0 dB/oct �
� 3 � 6.0 dB/oct �
읕컴컴좔컴컴컴컴컴컴�
bits 0-5: Output Level. Attenuates the operator output level. 0 is the
loudest, 3F is the softest. In additive synthesis, varying
the output level of any operator varies the volume of its
corresponding channel. In FM synthesis, varying the output level
of the carrier varies the volume of the channel. Varying the
output of the modulator will change the frequency spectrum
produced by the carrier.
The following table summarizes which operators' output levels
should be updated when trying to change channel output level.
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� Mode � Op 1 � Op 2 � Op 3 � Op 4 �
쳐컴컴컴탠컴컴컵컴컴컴탠컴컴컵컴컴컴�
� AM � � � � � N/A � N/A �
� FM � - � � � N/A � N/A �
� FM-FM � - � - � - � � �
� AM-FM � � � - � - � � �
� FM-AM � - � � � - � � �
� AM-AM � � � - � � � � �
읕컴컴컴좔컴컴컨컴컴컴좔컴컴컨컴컴컴�
60-75: Attack Rate / Decay Rate:
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� Attack Rate � Decay Rate �
聃컴좔컴좔컴좔컴좔컴좔컴좔컴좔컴1/2
bits 4-7: Attack Rate. Determines the rising time for the sound.
The higher the value, the faster the attack.
bits 0-3: Decay Rate. Determines the diminishing time for the sound.
The higher the value, the shorter the decay.
80-95: Sustain Level / Release Rate:
靈7컫�6컫�5컫�4컫�3컫�2컫�1컫�0캠
� Sustain Level � Release Rate �
聃컴좔컴좔컴좔컴좔컴좔컴좔컴좔컴1/2
bits 4-7: Sustain Level. Determines the point at which the sound ceases
to decay and chages to a sound having a constant level. The
sustain level is expressed as a fraction of the maximum level.
0 is the softest and F is the loudest sustain level.
Note that the Sustain-bit in the register 20-35 must be set for
this to have an effect.
bits 0-3: Release Rate. Determines the rate at which the sound disappears
after KEY-OFF. The higher the value, the shorter the release.
A0-A8: Frequency Number:
Determines the pitch of the note. Highest bits of F-Number are stored
in the register below.
B0-B8: Key On / Block Number / F-Number(hi bits):
靈7컫�6컫�5컫�4컫�3컫�2컫�1컫�0캠
� 쿖EY� Block Num.� Freq �
聃컴좔컴좔컴좔컴좔컴좔컴좔컴좔컴1/2
bit 5: KEY-ON. When 1, channel output is enabled.
bits 2-4: Block Number. Roughly determines the octave.
bits 0-1: Frequency Number. 2 highest bits of the above register.
The following formula is used to determine F-Number and Block:
F-Number = Music Frequency * 2^(20-Block) / 49716 Hz
NOTE: In four-operator mode only the register value of Operators 1 and 2
is used, value of Operators 3 and 4 in this register is ignored.
In other words: one channel uses only one frequency, block and KEY-ON
value at a time, regardless whether it is a two- or four-operator
channel.
BD: Tremolo Depth / Vibrato Depth / Percussion Mode / BD/SD/TT/CY/HH On:
靈7컫�6컫�5컫�4컫�3컫�2컫�1컫�0캠
튦re쿣ib쿛er쿍D 쿞D 쿟T 쿎Y 쿓H �
聃컴좔컴좔컴좔컴좔컴좔컴좔컴좔컴1/2
bit 7: Tremolo (Amplitude Vibrato) Depth. 0 = 1.0dB, 1 = 4.8dB.
bit 6: Frequency Vibrato Depth. 0 = 7 cents, 1 = 14 cents.
A "cent" is 1/100 of a semi-tone.
bit 5: Percussion Mode. 0 = Melodic Mode, 1 = Percussion Mode.
bit 4: BD On. KEY-ON of the Bass Drum channel.
bit 3: SD On. KEY-ON of the Snare Drum channel.
bit 2: TT On. KEY-ON of the Tom-Tom channel.
bit 1: CY On. KEY-ON of the Cymbal channel.
bit 0: HH On. KEY-ON of the Hi-Hat channel.
NOTE: KEY-ON bits of channels 6, 7 and 8 must be clear and their
F-Nums, Attack/Decay/Release rates, etc. must be set properly
to use percussion mode.
C0-C8: FeedBack Modulation Factor / Synthesis Type:
靈7컫�6컫�5컫�4컫�3컫�2컫�1컫�0캠
� � R � L � FeedBack 쿞yn�
聃컴좔컴좔컴좔컴좔컴좔컴좔컴좔컴1/2
bit 5: Right Speaker Enable. When set, channel output goes to right
speaker.
bit 4: Left Speaker Enable. When set, channel output goes to left
speaker. At least one of these bits must be set to hear
the channel.
These two bits can be used to realize sound "panning", but this
method offers only three pan positions (left/center/right).
These bits apply only to operators producing sound (Carriers).
Modulators are not affected by their setting.
bits 1-3: FeedBack Modulation Factor. If 0, no feedback is present. If 1-7,
operator 1 will send a portion of its output back into itself.
旼컴컴컴컴컫컴컴컴컴�
� FeedBack � Factor �
쳐컴컴컴컴컵컴컴컴컴�
� 0 � 0 �
� 1 � �/16 �
� 2 � �/8 �
� 3 � �/4 �
� 4 � �/2 �
� 5 � � �
� 6 � 2檻 �
� 7 � 4檻 �
읕컴컴컴컴컨컴컴컴컴�
When in four-operator mode, the FeedBack value is used only by
Operator 1, value of Operators 2, 3 and 4 is ignored.
bit 0: Synthesis Type. 1 = Additive synthesis, 0 = Frequency Modulation
In four-operator mode, there are two bits controlling the
synthesis type. Both are the bit 0 of register C0, one of
Operators 1 and 2 and the second of Operators 3 and 4.
旼컴컴컴컫컴컴컴컴쩡컴컴컴커
� Op 1&2 � Op 3&4 � Type �
쳐컴컴컴컵컴컴컴컴탠컴컴컴캑
� 0 � NONE � FM �
� 1 � NONE � AM �
� 0 � 0 � FM-FM �
� 1 � 0 � AM-FM �
� 0 � 1 � FM-AM �
� 1 � 1 � AM-AM �
읕컴컴컴컨컴컴컴컴좔컴컴컴켸
E0-F5: Waveform Select:
靈7컫�6컫�5컫�4컫�3컫�2컫�1컫�0캠
� � WaveForm �
聃컴좔컴좔컴좔컴좔컴좔컴좔컴좔컴1/2
bits 0-2: WaveForm Select (WS):
WaveForm 0: Sine WaveForm 1: Half-Sine
� /~\ � /~\ /~\
�/ \ / �/ \ / \
�/컴컴�\컴컴�/컴 컵컴컴컨-----좔컴컴좔
� \ / �
� \_/ �
WaveForm 2: Abs-Sine WaveForm 3: Pulse-Sine
� /~\ /~\ � /~| /~|
�/ \ / \ / �/ | / |
컵컴컴컨컴컴컨컴 컵컴컨-------좔컴좔컴
� �
� �
WaveForm 4: Sine - even periods only
� /~\ /~\
�/ \ / \
컵컴컴�\컴컴컫-----------좔컴컴\컴컴컫�
� \ / \ /
� \_/ \_/
WaveForm 5: Abs-Sine - even periods only
� /~\ /~\ /~\ /~\
�/ \ / \ / \ / \
컵컴컴컨컴컴컨-----------좔컴컴좔컴컴좔
�
�
WaveForm 6: Square
�-----� �-----� �-----� �-
� | | | | | |
컵컴컴�|컴컴�|컴컴�|컴컴�|컴컴�|컴컴�|컴
� | | | | | |
� �-----� �-----� �-----�
WaveForm 7: Derived Square
� |\ |\
� | \ | \
컵--__컴컴|컴컴~~-----__컴컴|컴컴~~-----
� \ | \ |
� \| \|
NOTE: Bit 5 of register 01 must be set to use waveforms other than sine.
Waveforms 4-7 are available only on OPL3.
See files WAVEn.GIF for real waveforms, where n is a number between
0 and 7.
APPENDIX A - EXAMPLES
---------------------
These examples show a few working routines used in my MUS Player.
They are written in Borland C++ 3.1 but should be easy to translate to any
other language.
--------------------------------- cut here ---------------------------------
// I prefer using these Assembler-like types
typedef unsigned int WORD;
typedef unsigned char BYTE;
/*
* FM Synthesizer base port. SB Pro II - 0x220, Adlib 0x388
*/
WORD FMport = 0x220;
/*
* Enables OPL3 extensions.
*/
WORD OPL3 = 1;
/*
* Direct write to any Adlib/SB Pro II FM synthetiser register.
* reg - register number (range 0x001-0x0F5 and 0x101-0x1F5). When high byte
* of reg is zero, data go to port FMport, otherwise to FMport+2
* data - register value to be written
*/
BYTE FMwriteReg(WORD reg, BYTE data)
{
asm {
mov dx,FMport
mov ax,reg
or ah,ah // high byte is nonzero -- write to port base+2
jz out1
inc dx
inc dx
}
out1: asm {
out dx,al
mov cx,6
}
loop1:asm { // delay between writes
in al,dx
loop loop1
inc dx
mov al,data
out dx,al
dec dx
mov cx,36
}
loop2:asm { // delay after data write
in al,dx
loop loop2
}
return _AL;
}
/*
* Write to an operator pair. To be used for register bases of 0x20, 0x40,
* 0x60, 0x80 and 0xE0.
*/
void FMwriteChannel(BYTE regbase, BYTE channel, BYTE data1, BYTE data2)
{
static BYTE adlib_op[] = {0, 1, 2, 8, 9, 10, 16, 17, 18};
static BYTE sbpro_op[] = { 0, 1, 2, 6, 7, 8, 12, 13, 14,
18, 19, 20, 24, 25, 26, 30, 31, 32};
static WORD rg[] = {0x000,0x001,0x002,0x003,0x004,0x005,
0x008,0x009,0x00A,0x00B,0x00C,0x00D,
0x010,0x011,0x012,0x013,0x014,0x015,
0x100,0x101,0x102,0x103,0x104,0x105,
0x108,0x109,0x10A,0x10B,0x10C,0x10D,
0x110,0x111,0x112,0x113,0x114,0x115};
if (OPL3)
{
register WORD reg = sbpro_op[channel];
FMwriteReg(rg[reg]+regbase, data1);
FMwriteReg(rg[reg+3]+regbase, data2);
} else {
register WORD reg = regbase+adlib_op[channel];
FMwriteReg(reg, data1);
FMwriteReg(reg+3, data2);
}
}
/*
* Write to channel a single value. To be used for register bases of
* 0xA0, 0xB0 and 0xC0.
*/
void FMwriteValue(BYTE regbase, BYTE channel, BYTE value)
{
static WORD ch[] = {0x000,0x001,0x002,0x003,0x004,0x005,0x006,0x007,0x008,
0x100,0x101,0x102,0x103,0x104,0x105,0x106,0x107,0x108};
register WORD chan;
if (OPL3)
chan = ch[channel];
else
chan = channel;
FMwriteReg(regbase + chan, value);
}
--------------------------------- cut here ---------------------------------
APPENDIX B - DETECTION METHODS
------------------------------
An official method of Adlib (OPL2) detection is:
1. Reset Timer 1 and Timer 2: write 60h to register 4.
2. Reset the IRQ: write 80h to register 4.
NOTE: Steps 1 and 2 can't be combined together.
3. Read status register: read port base+0 (388h). Save the result.
4. Set Timer 1 to FFh: write FFh to register 2.
5. Unmask and start Timer 1: write 21h to register 4.
6. Wait in a delay loop for at least 80 �sec.
7. Read status register: read port base+0 (388h). Save the result.
8. Reset Timer 1, Timer 2 and IRQ as in steps 1 and 2.
9. Test the results of the two reads: the first should be 0,
the second should be C0h.
If either is incorrect, then the OPL2 is not present.
NOTE1: You should AND the result bytes with E0h because the unused bits
are undefined.
NOTE2: This testing method doesn't work in some SoundBlaster compatible cards.
OPL3 DETECTION
--------------
0. Detect OPL2. If present, continue.
1. Read status register: read port base+0.
2. AND the result with 06h.
3. If the result is zero, you have OPL3, otherwise OPL2.
NOTE: This is NOT an official method. I have dug it out of a sound driver.
I haven't tested it, because I haven't an OPL2 card (Adlib, SB Pro I).
Nevertheless it "detects" my SB Pro II properly. ;-)
Another possible detection method for distinguishing between SB Pro I and
SB Pro II would be to try to detect OPL2 at I/O port base+0 and then at port
base+2. The first test should succeed and the second should fail if OPL3 is
present. (Remember: SB Pro I contains twin OPL2 chips at addresses base+0 and
base+2, while SB Pro II contains one OPL3 chip at I/O address base+0 thru
base+3).
BLASTER ENVIRONMENT VARIABLE
----------------------------
Perhaps the most recommended "detection" method. Reading this variable avoids
blindfold I/O port scanning and possible device conflicts. The user is
responsible for its proper setting.
The variable has this format:
BLASTER=Aaddr Iirq Ddma Ttype
A: Base I/O address given in hex. For most Sound Blasters the default is 220.
I: IRQ Number (decimal). Default 7.
D: DMA Number (decimal). Default 1.
T: Card Type (decimal):
1 - Sound Blaster 1.5
2 - Sound Blaster Pro I
3 - Sound Blaster 2.0
4 - Sound Blaster Pro II
Example:
BLASTER=A220 I7 D1 T4
REFERENCES
----------
Title: The PC Games Programmers Encyclopedia
Authors: Mark Feldman and many others on Usenet and Internet
FTP: teeri.oulu.fi
/pub/msdos/programming/gpe
... you can find (almost) everything you need there
Title: Sound Blaster - The Official Book
Authors: Richard Heimlich, David M. Golden, Ivan Luk, Peter M. Ridge
Publishers: Osborne/McGraw Hill
ISBN: 0-07-881907-5
... this is a number-one in my book-wishlist. If anyone wanted to get rid of
the book, I wouldn't scorn it ... :-)
Title: The SoundBlaster Developer Kit
Publishers: Creative Labs Inc
Creative Technology PTE LTD
... I wonder if you can find something comprehensible in that.
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