CALL SET PCM
This page was last modified 22:27, 21 October 2019 by Mars2000you.

Contents

Effect

Initialises an ADPCM/PCM file to be used as sound instrument (voice).

Syntax

CALL SET PCM(<voice file>,<device>,<mode>,<specific parameter>,<length>[,<sampling frequency>][,<channel>])

Parameters

<voice file> is a number between 0 and 15, that specifies the ADPCM/PCM file. This number is also used in the following instructions: CALL CONVA - CALL CONVP - CALL COPY PCM - CALL LOAD PCM - CALL MK PCM - CALL PLAY PCM - CALL REC PCM - CALL SAVE PCM.

<device> is a number between 0 and 5, that specifies the location of the ADPCM/PCM file.

According the used device, the three next parameters can vary (and sometimes are not used).

Device Name Mode Specific parameter Length
0 Sample RAM of first MSX-AUDIO chip 0 or 1 not used used
1 Sample ROM of first MSX-AUDIO chip not used ROM audio file number used
2 Sample RAM of second MSX-AUDIO chip 0 or 1 not used used
3 Sample ROM of second MSX-AUDIO chip not used ROM audio file number used
4 Computer RAM 0 or 1 Array name not used
5 Computer VRAM 0 or 1 Address used


<mode> specifies the PCM mode (it is not used for files in Sample ROM as all these files have a built-in mode parameter):

  • 0 = ADPCM
  • 1 = PCM

<specific parameter> is not used for files in Sample RAM. Otherwise, it specifies

  • the ROM audio file number (between 0 and 29) when Sample ROM is used - 18 ADPCM voices are built-in in the Sample ROM (see below Sample ROM ADPCM Voice Data Table) and the MSX-AUDIO Sample ROM can contain a maximum of 30 ADPCM/PCM voices.
  • the array name for files in computer RAM
  • the address for files in computer VRAM.

<length> is not used for files in computer RAM. The unit of length is 256 bytes.

<sampling frequency> is exprimed in Hz and can vary from 1800 to 16000. However, when you want to play an ADPCM file in local mode, using the Sample RAM or the Sample ROM, the sampling frequency can vary from 1800 to 49716. The default value is 8000 Hz.

<channel> specifies the MSX-AUDIO channel for recording and playback:

  • 0 = channel of first MSX-AUDIO chip
  • 1 = channel of second MSX-AUDIO chip

When omitted, the device is not connected if you use device 0 to 3. For files in computer RAM or VRAM, channel 0 is used by default.

Note: after initialisation with CALL AUDIO, audio file number 0 is assigned to the Sample RAM of the first MSX-AUDIO chip and the other audio files have a length of 0. It is equivalent to CALL SET PCM(0,0,0,,128)

Sample ROM ADPCM Voice Data Table

This is a list of the voices available in the built-in MSX-AUDIO Sample ROM.

Voice No. Name Offsets Bytes Voice No. Name Offsets Bytes
0 Cuckoo 35 8960 9 Footsteps 1 256
1 Chicken 33 8448 10 Progress 6 1536
2 Cat 20 5120 11 Toy 4 1024
3 Dog 5 1280 12 Applause 2 512
4 Horse 29 7424 13 Tennis 5 1280
5 Lion 43 11008 14 Golf swing 9 2304
6 Laughing people 26 6656 15 Golf cup-in 9 2304
7 Closing of a door 11 2816 16 Sword being waved 1 6 1536
8 Whiskey being poured 4 1024 17 Sword being waved 2 7 1792


Directory structure for each voice in Sample ROM

Bytes Content Values
0 Voice type 0 = ADPCM - 128 = PCM
1 Reserved 0
2-3 Start Adddress
4-5 Data Length
6-7 Sampling Frequency


General structure of Sample ROM

Bytes Content Values
0-1 AB Signature 41/42
2-15 Reserved 0
16-23 Directory for voice 0
24-31 Directory for voice 1
etc...
240-247 Directory for voice 29
248-255 Directory end mark 0
256 and higher Audio data


Examples

CALL SET PCM(0,0,0,,32)
10 SCREEN 0: KEYOFF: CALL AUDIO
20 FOR N=0 TO 17:READ L,T
30 CALL SET PCM (0,0,0,,L)
40 CALL COPY PCM (#N,0)
50 CLS
60 LOCATE 5,12: PRINT "Sample nr ";N
70 LOCATE 5,15: PRINT "Spacebar for next sample"
80 LOCATE 5,18: PRINT "ESC to stop"
90 CALL PLAY PCM (0)
100 K$=INKEY$
110 IF K$=CHR$(32) THEN 150
120 IF K$=CHR$(27) THEN 170
130 FOR J=1 TO T: NEXT J
140 GOTO 90
150 CALL STOPM
160 NEXT N
170 END
180 DATA 35,0,33,1500,20,1300,5,200,29,1200,43,1500,26,1700,11,1000,4,110
190 DATA 1,500,6,250,4,80,2,80,5,600,9,1000,9,1000,6,900,7,900

Related to

CALL AUDIO, CALL CONVA, CALL CONVP, CALL COPY PCM, CALL LOAD PCM, CALL MK PCM, CALL PCM FREQ, CALL PLAY PCM, CALL REC PCM, CALL SAVE PCM

Compatibility

MSX-AUDIO BASIC