Chapter 1 Basic Overview

• " Sound Driver Ver.2.20 Programmer's Guide " is a technical document for programmers. Please take a look through it. Important information about sound processing is explained.

• Please be sure to use the latest sound driver ( Ver.2.04 or later ) except for projects that are about to be released. If you are forced to use an earlier version due to data compatibility issues, only version 1.33B is available.
  Please also match the driver version when creating the data and when incorporating it into the game.
  The version of the sound driver you are using is written in ASCII code if you dump 1020h from the beginning of the driver in hexadecimal.
  To identify it from SndSimlator, open "About this SndSimlator" from the Apple menu.

• There are three things you should refer to if the sound doesn't work as expected or you're having trouble.
  1. Command history
  2. error status bit
  3. Other sound WORK RAM information such as mode, status etc.
  For details on these, please refer to the " Sound Driver Ver. 2.20 Programmer's Guide ".

• Trouble with submissions in case of sound trouble,
  1. Troubles that can be reproduced using Mac tools
  2. This is normal on the tool, but problems occur when incorporating it into the game.
  Broadly speaking, in case 1, what to submit at the time of trouble is
  Complete set of development data on Mac
  1. Sound simulator map file
  2. Tone editor tone file (if there is a .bin file)
  3. DSP Linker .YLI file (.EXB file if available)
  4. STANDARD MIDI FILE (Type1) output from the sequencer
  5. Description document
  For 2, in addition to A, B, C, D, and E

  6. CD-ROM that can reproduce the phenomenon and explanation of how to reproduce it
  I would like to have it.

• 3 ways to control sound from SH2
  1. Uses functions from SBL (including PCM and ADPCM playback libraries) library
  2. Use functions from SGL library
  3. Write commands directly in the command area without using a sound library

• Basically, the sound tool will not malfunction depending on the Macintosh model, whether PowerMac or 68x00Mac. The biggest cause of trouble with sound tools is SCSI-related. To avoid problems as much as possible, connect the Macintosh and Sound Box with the shortest possible high-quality SCSI cable, and avoid connecting any SCSI devices that are not in use. Also, in a CartDev. environment, if MIDI signals and SCSI transfers are frequently performed at the same time, it is likely to freeze, so please avoid this as much as possible.

• The TONE editor and DSP linker will not work unless you transfer the sound map using SndSimulator and start the sound driver. This is because the TONE editor and DSP linker function by referring to the set address and size of the transferred map tone BANK and DSP work RAM.
  The waveform editor simply uses the SoundBox's RAM as a work area, so there is no need to transfer the sound map or start the sound driver. While using the waveform editor, some of the LEDs 1 to 8 on the back of the sound box will remain lit, which is normal. The waveform editor uses the area after address 10000H as its work area and destroys it. If you use the Tone editor or DSP linker again, please transfer the data again as necessary.

• The sound simulator's PCM stream playback is also simulated using SCSI transfer, so it may sound different from the actual device. Please consider this function to be only a simple feature.

• For Sound Box (Sound Board System), Start up simply calls Go to the sound driver, and the sound driver is transferred when SndSimulator is started.

• SndSim2.0 or later only works with Driver 1.29i or later. Older sound drivers cannot be used.

• The 4 sets of LEDs (32K, 44.1K, 48K, PARITY, DE-EMP indications) on the Sound Box (Sound Board System) do not affect the operation of the sound tool no matter what state they are in. 32K, 44.1K, and 48K light up in accordance with the sampling rate of the sound box's optical input. Inputs other than 44.1kHz are possible, but operation is not guaranteed, so please refrain from doing so.

• LED specifications on the back of Sound Box (Sound Board System)
  When the boot ROM starts up, LEDs 1 to 8 flash while moving. While data is being transferred using SCSI, this operation will stop momentarily, but will resume after the transfer is complete.
  After transferring the driver to the target, when you run the program, LED1 will blink, confirming that the CPU is operating normally.

  When LED1 is blinking (CPU is operating normally), the meanings of other LEDs blinking are as follows.

  LED2: CPU processing capacity MAX

  LED3: BGM decompression interrupt driving (normally blinking).

  LED4: no care

  LED5: no care

  LED6: no care

  LED7: MIDI input from MIDI-IN2 on the board.

  LED8: MIDI input from MIDI-IN1 on the board.

  Also, when LED1 is off, other LEDs blinking means the following error (if it remains lit, SCSI communication is in progress or the driver is HALT).

  LED number 12345678	meaning
  	YM3802(MIDI-1) IRQ vector error
  	// (MIDI-2) //
  	MIDI data error
  	YM3802(MIDI-1) MIDI out error
  	// (MIDI-2) //
  	MIDI Control change $60～$7F input
  	HOST I/F Command execute error
  	...........
  	...........
  	Map change error
  	BANK change error
  	MIXER change error
  	EFFECT change error
  	68k un-definition vector event
  	...........
  	68k buss error
  	68k address error
  	...........
  	68k level-3 event
  	68k level-4 event
  	68k level-7 event

• The 16Bit, 11.3MHz clock 68EC000 controls the SCSP as a dedicated CPU for sound control. 68EC000 is directly connected to SCSP and operates independently from SH2. SCSP can also be accessed from SH2. Neither SCSP nor the 68000 will stop during access, but due to time-sharing processing, if there is a large amount of access from SH2, the processing capacity of the 68000 will decrease.

• The SCSP chip's clock is 22.58MHz, and the 68000's clock is 11.3MHz.
  Also, regarding the CPU execution unit time of the sound driver,

  The execution unit time of software DSP control is 8 msec.

  The execution unit time of the software PLFO is 4 msec.

  The execution unit time of other target programs is 2msec.

• PCM data size brief knowledge
  88 kbyte per second at 16bit44.1kHz (about 5 seconds at 450 kbyte, which is almost the maximum sound RAM).
  11kbyte per second at 8bit11kHz (approximately 40 seconds at 450kbyte, which is almost the maximum sound RAM).
  In SCSP, one waveform is up to 64ksample, so for both 16bit and 8bit, it takes 0.72 seconds at 44.1kHz and 2.9 seconds at 11kHz.