Network protocol for Impulse Tracker

Impulse Tracker will only interface with similar versions of IT.

Block format

Offset  Size    Meaning
0       Word    Block type
2       Word    Block length
4       Data    Basic data, depending on block type.
x+[2]   Word    CRC Check

Block types

様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様
Block type 0 - Acknowledge receipt - targeted
陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳

Offset  Size    Meaning
0       Word    Block type received
2       Word    Status

Status: Bit 0 = Off = OK, On = resend

様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様
Block type 1 - Ping
陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳

Offset  Size    Meaning
0       String  "Impulse Tracker 2.?? Ping Packet"

様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様
Block type 2 - Pattern data packet - global
陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳

Offset  Size    Meaning
0       Byte    Pattern number
1       Byte    Row
2       Byte    Column
3       Byte    Data mask
4       Varies  Data

Data mask
 Bit 0: Note
 Bit 1: Instrument
 Bit 2: Volume
 Bit 3: Effect
 Bit 4: Effect data

Absence of information does NOT imply clearing.

様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様
Block type 3 - Pattern data block packet - global
陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳

Offset  Size    Meaning
0       Byte    Pattern number
1       Byte    Block width
2       Byte    Block height
3       Varies  Data

Data is a block_width * block_height array as structured:

Data mask:
 Bit 0: Note
 Bit 1: Instrument
 Bit 2: Volume
 Bit 3: Effect
 Bit 4: Effect data

Absence of information DOES imply clearing.

様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様
Block type 4 - "Song Segment variable" modification - global
陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳

Offset  Size    Meaning
0       Word    Offset in SongSegment
2       Word    Length of data
4       Varies  Data

様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様
Block type 5 - Sample data - global
陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳

Offset  Size    Meaning
0       Word    Sample number
4       DWord   Offset in sample
8       Varies  Data

様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様
Block type 6 - Chat packet - targeted/global
陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳陳

Offset  Size    Meaning
0       Word    Length of data
2       Varies  Data


様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様
                       Functions required of the drivers
様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様

Initialise - basic setup code. Return error if driver unavailable in current
             environment.
Connect Interface - provides connection interface, sets up a tracking
                    connection, returns a handle
Management Interface - provides management interface for connection,
                       status information etc.
Disconnect - shut down a tracking connection to a particular handle
MaximumPacketSize - returns the maximum size in bytes that the driver can
                    process at any time.
Send data - given handle (0 = send to all), data packet (a maximum size as
            returned by MaximumPacketsize)
Receive data poll - called frequently by the main program to check for
                    incoming data. Approx. 2nd highest priority (after
                    sound driver IRQ)

様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様
                       Functions provided to the drivers
様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様様

ProcessDataReveived - called when any data is received.
UnloadDriver - remove driver from memory (when no connections exist any longer)
Alert - when data is not being transferred.