org.jsynthlib.synthdrivers.AlesisQS

Class SysexRoutines

java.lang.Object

org.jsynthlib.synthdrivers.AlesisQS.SysexRoutines

public class SysexRoutines
extends Object

Routines to help with Sysex'es. Alesis compresses data to save space This is taken from the manual.

Data is in a packed format in order to optimize data transfer. Eight MIDI bytes are used to transmit each block of 7 QS data bytes. If the 7 data bytes are looked at as one 56-bit word, the format for transmission is eight 7-bit words beginning with the most significant bit of the first byte, as follows:

SEVEN QUADRASYNTH BYTES:
0: A7 A6 A5 A4 A3 A2 A1 A0
1: B7 B6 B5 B4 B3 B2 B1 B0
2: C7 C6 C5 C4 C3 C2 C1 C0
3: D7 D6 D5 D4 D3 D2 D1 D0
4: E7 E6 E5 E4 E3 E2 E1 E0
5: F7 F6 F5 F4 F3 F2 F1 F0
6: G7 G6 G5 G4 G3 G2 G1 G0

TRANSMITTED AS:
0: 0 A6 A5 A4 A3 A2 A1 A0
1: 0 B5 B4 B3 B2 B1 B0 A7
2: 0 C4 C3 C2 C1 C0 B7 B6
3: 0 D3 D2 D1 D0 C7 C6 C5
4: 0 E2 E1 E0 D7 D6 D5 D4
5: 0 F1 F0 E7 E6 E5 E4 E3
6: 0 G0 F7 F6 F5 F4 F3 F2
7: 0 G7 G6 G5 G4 G3 G2 G1

Version:

$Id: SysexRoutines.java 745 2004-10-03 18:17:58Z hayashi $

Author:

Zellyn Hunter (zellyn@bigfoot.com, zjh)

Constructor Summary

Constructors

Constructor and Description
SysexRoutines()

Method Summary

Modifier and Type	Method and Description
static char	decodeChar(int charCode) Given an Alesis character code for a character, return the character it represents
static int	encodeChar(char ch) Given a character, return the Alesis character code that represents it
static int	getBits(byte[] sysex, int headerCount, int msBit, int bitSize, boolean signed) Given a compressed sysex, retrieve a run of consecutive bits as an integer
static String	getChars(byte[] sysex, int headerCount, int msBit, int count) Given a compressed sysex, retrieve a run of consecutive characters, starting at the given bit
static void	setBits(int value, byte[] sysex, int headerCount, int msBit, int bitSize) Given a compressed sysex, set a run of consecutive bits to a value
static void	setChars(String chars, byte[] sysex, int headerCount, int msBit, int count) Given a compressed sysex, set a run of consecutive characters, starting at the given bit.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SysexRoutines

public SysexRoutines()

Method Detail

getBits

public static int getBits(byte[] sysex,
                          int headerCount,
                          int msBit,
                          int bitSize,
                          boolean signed)

Given a compressed sysex, retrieve a run of consecutive bits as an integer

Parameters:

sysex - the actual bytes of the sysex message

headerCount - how many bytes of the sysex are used up as a header - compression starts after the header

msBit - the starting (most significant) bit

bitSize - the number of bits to return - 1 to 8

signed - if true, take the two's complement of the result

Returns:

int the value of the requested bits

setBits

public static void setBits(int value,
                           byte[] sysex,
                           int headerCount,
                           int msBit,
                           int bitSize)

Given a compressed sysex, set a run of consecutive bits to a value

Parameters:

value - the integer value to set the bits to

sysex - the actual bytes of the sysex message

headerCount - how many bytes of the sysex are used up as a header - compression starts after the header

msBit - the starting (most significant) bit

bitSize - the number of bits to return - 1 to 8

getChars

public static String getChars(byte[] sysex,
                              int headerCount,
                              int msBit,
                              int count)

Given a compressed sysex, retrieve a run of consecutive characters, starting at the given bit

Parameters:

sysex - the actual bytes of the sysex message

headerCount - how many bytes of the sysex are used up as a header - compression starts after the header

msBit - the starting (most significant) bit

count - the number of characters to return

Returns:

the uncompressed and decoded characters

setChars

public static void setChars(String chars,
                            byte[] sysex,
                            int headerCount,
                            int msBit,
                            int count)

Given a compressed sysex, set a run of consecutive characters, starting at the given bit. If chars has more characters than count, set only count characters

Parameters:

chars - the characters to set

sysex - the actual bytes of the sysex message

headerCount - how many bytes of the sysex are used up as a header - compression starts after the header

msBit - the starting (most significant) bit

count - the maximum number of characters to set

decodeChar

public static char decodeChar(int charCode)

Given an Alesis character code for a character, return the character it represents

Parameters:

charCode - the code for the character, as stored in the Alesis

Returns:

the char represented by charCode

encodeChar

public static int encodeChar(char ch)

Given a character, return the Alesis character code that represents it

Parameters:

ch - the character

Returns:

the Alesis character code that represents ch