Accell MPC-LNK Computer Hardware User Manual


 
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MPC-LNK
MPCLNK is a network board with an objective of sharing memory data and bit-unit information. By using MPCLNK, connected equipment (personal
computers and MPC-68K) can share 249-byte memory. Also, because a function is included for transferring data by block to a specified address,
individual communications that used to be performed by RS-232C etc. are supported together by MPCLNK. The number of connectable units is up
to 16. When MPCLNK and LNK-048 are combined, one unit of MPCLNK and up to 15 units of LNK-048 are connectable.
The response speed is within 10 msec for transferring a shared variable from #1 to any other, and is the number of connection * 10 msec for changing a shared
variable of #2-#15 except #1 or for the input status of LNK-048 to be returned to #1. In the case of up to five-unit connection which is a default factory ship-
out condition, the response speed is within 50 msec.
As for the distance of the communication cable, because it is based on RS-485 standard, the connection will have no problem up to several hundred meters.
Also, the communication interface is isolated by a pulse transformer, preventing noise trouble etc. that occurs when used by different power sources.
Connection Method
Because MPCLNK adopted an interface based on RS-485, it
can be easily connected via twisted-pair cables. Two connectors
and a short pin for a terminator belong to MPCLNK, and they
are connected as in the figure. What should be kept in mind is
for the connection to be in a cascade as in the figure and to set
the terminator ON (the short pin is shorted) for the MPCLNKs
at the ends.
PC (AT, 98) + LNK-048
This is a remote IO for a personal computer. One LNK-048 is equipped with
24-point input and 24-point output, and can perform reading of input from
the host side and control of the output port. The host needs one MPCLNK,
and the I/O unit and MPCLNK are connected via a twisted-pair cable. Because
communication is done through an RS-485 interface, connection of plural
LNK-048 is simple by multiple-drop bus connections of a twisted pair.
Control and reading of the IO are performed via the UMB area of the personal
computer (this is because MPCLNK works as a memory installed in the UMB
area). Writing into the UMB area is reflected as is by the output port of
LNK-048, and the input content of LNK-048 is reflected as is by the specified
memory of the UMB. Therefore, the I/O can be directly controlled using
application software for DOS/WINDOWS etc.
MPC-68K + LNK-048
LNK-048 is a remote IO of MPC-68K. One LNK-048 is equipped with 24-
point input and 24-point output, and can perform reading of input from the
68K side and control of the output port. The host needs one MPCLNK, and
the I/O unit and MPCLNK are connected via a twisted-pair cable. Because
communication is done through RS-485 interface, connection of plural LNK-
048 is simple by multiple-drop bus connections of a twisted pair. For control
and reading of IO, the IO commands such as ON/OFF, SW(), etc. of MPC-
68K are available.
LNK-048 + LNK-048
By using LNK-048 one on one, the I/O condition can be transmitted as it is to a
distant place. The 24-point input content to one is reflected by the output of the
other. Connection of LNK-048 is by one twisted pair, withstanding even a distance
of several hundred meters (in the case of an RS-485 standard cable). Also, if the IO
link destination is fixed, two or more LNK-048 can be IO-connected (customization
will be necessary).
SP10
shorted
SP10
open
SP10
shorted
SP10
open
J
2
J
3
J
2
J
3
J
2
J
3
J
2
J
3
EA
A
O
LNK-048
MP C - LNK
PC-LNK
LNK-048
Twisted pair
LNK
-
048
M
P
C
-
LNK
M
P
C
-
68
K
LNK
-
048
Twisted pair
CEP
-
041
L
N
K
-
048
L
N
K
-
048