Kurzweil K2661, Справочник музыканта

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System Exclusive Protocol
K2661 System Exclusive Implementation
7-3
The bit-stream format can be thought of as taking the binary bits of the K2661 data and, starting
from the left, slicing off groups of 7 bits. Note that the trailing bits are set to zero.
After the
data
fi eld, there is another fi eld,
xsum
. This is a checksum fi eld that is calculated as the
least signi fi cant 7-bits of the sum of all of the MIDI bytes that make up the
data
fi eld.
Messages
This section de fi nes the K2661 System Exclusive message formats. Each message has a message
type, which goes in the
msg-type
fi eld (see Common Format on page 7-1), followed by the fi eld
de fi nitions of the message.
DUMP = 00h type(2) idno(2) offs(3) size(3) form(1)
Requests the K2661 to send a data dump of an object or portion thereof.
type
and
idno
identify
the object.
offs
is the offset from the beginning of the object’s data;
size
describes how many
bytes should be dumped starting from the offset.
form
indicates how the binary data are to
transmitted (0=nibblized, 1=bit stream). The response is a LOAD message:
LOAD = 01h type(2) idno(2) offs(3) size(3) form(1) data(n) xsum(1)
This writes data into the speci fi ed object, which must exist. Both load and dump operate on the
object data only. The response to a load message will be the following:
DACK = 02h type(2) idno(2) offs(3) size(3)
Load accepted, or
DNAK = 03h type(2) idno(2) offs(3) size(3) code(1)
Load not accepted. The
code
fi eld indicates the cause of the failure, as follows:
To request information about an object, use:
DIR = 04h type(2) idno(2)
The
type
and
idno
identify the object. The response is an INFO message:
INFO = 05h type(2) idno(2) size(3) ramf(1) name(n)
This is the response to DIR, NEW, or DEL. If object is not found,
size
will be zero and
name
will
be null.
ramf
is 1 if the object is in RAM.
Code Meaning
1 Object is currently being edited
2 Incorrect checksum
3 ID out of range (invalid)
4 Object not found (no object with that ID exists)
5 RAM is full