Roland MT-32 Owner's Manual page 35

tt
Rejection
:
RJC (4FH)
This
message
is
sen!
qui
when
ihcre
is
a
need
to
terminate
communicaiion
Ijy
overriding Ihc current message.
An RJC
message
will
be [riggercd
when
:
a
WSD
or
ROD
message
has specified
an
illegal
dala address
or
size,
or the device
is
not
ready
for
communication.
an
illegal
number
of
addresses or data
has been
detected.
data transfer has been
terminated by an operator.
a communications error
has occurred.
An ERR
message
may be
sen!
out by a device on either side
of
the interface
.
Communication must
be
terminated
immediately
when
cither side triggers
an
ERR
message.
Byte
Description
FOH Exclusive status
41H Manufactures
10
(Roland)
DEV
Device
ID
MDL
Model ID
4FH
Command
ID
F7H End of exclusive
#
Example
of
Message Transactions
•
Data
transfer
from device (A) to device
(B).
Device (A)
Device
(B)
{Want
to
send
data]
{Data
set]
[Data
set)
{End of data]
iaj
—
(Acknowledge]
[Acknowledge]
[Acknowledge]
[Acknowledge]
•
Error
occurs
while
device (A)
is
receiving data
from
device
(8).
I)
Data transfer
from
device (A) to
device
<B).
Device (A) Device (B)
[Acknowledge]
(Error)
x
—
t-
(Communication error]
[Data
set]
[Data set]
[Data
set]
[Acknowledge]
(the
same
data
*"
as
above)
2)
Oevice (B) rejects the data re-transmitied,
and
completes data
transfer.
Device (A) Device (B)
[Acknowledge]
(Error)
x
-mi
—
[Communication
error }-
(Complete)
*
[Data
set]
[Data set]
[Rejection]
3) Device
(A) immediately completes data
transfer.
Device (A)
Device
(B)
[Acknowledge]
(Error)
x
[Rejection]
[Data set)
[Data set]
*-
(Complete)
i
Device (A) requests and receives data
from
device
(B).
Device (A)
[Request data)
[Acknowledge]
[Acknowledge]
[Acknowledge]
Device
(B)
[Data
set]
[Data set]
[End
of data]