Accell MPC series User Manual

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MPC-LNK, PC-LNK
Communication Board
(98 C-Bus Standard) / PC-LNK (ISA)
[Characteristics]
MPC-LNK (PC-LNK) is a data network connecting our MPC-68K, NEC PC98 series, and
DOS/V machines.  Unlike networks by other specifications, it does not let the host generate
interruptions or consume system memory.  MPC-LNK itself becomes a RAM board connected
via communication, both the connected 68K and personal computer having shared variables
usable in common.
The connection interface uses RS-485 (750 kpps SDLC standard), where a network can be
easily constructed by a twisted-pair multiple drop (the maximum connection length is 1.2
km according to the RS-485 specification).  MPC-LNK can be utilized not only as a pure
68K network but also as a data exchange network for personal computers using libraries.
Shared variables
These are common variables of 249 bytes which all MPC-LNK can refer to.  Shared variables
are refreshed every 24 sec and can be changed or referred to at real time.  The content set by
the #1 station circulates to the whole every 10 msec, and the content changed by the #2 or
latter station is reflected by the whole every n * 10 msec (n is the number of MPC-LNKs
connected to the network, whose default value is 5).  Also, 68K deals with them as 125 word-
type variables.
Mail forwarding
All the connected MPC-LNKs can perform block transfers by 250-byte units.  In forwarding
mail, the receipt status, forwarding, and read-out by the recipient can be confirmed.
[Specification] Communication
RS-485/SDLC standard 750 kpps.  SN75176B used.
Pulse transformer isolated.
Cable
Shielded twisted pair to be used (60 nF/km)
Bus I/F
MPCLNK: 68K system bus / PC-98 expansion bus standard (full decoding).
PC-LNK: ISA bus.  Installed in the UMB area as memory.
Address
68K: 1000H, 2000H fixed (I/O area).
PC98 / DOS/V: C0000H~ (expanded ROM area 0~BFFH exclusive).
Memory
Shared variables
249 bytes
Send-mail buffer
250 bytes
Receive-mail buffer
250 bytes
Consumed current
150 mA
[Accessories]
(1) Power connectors (H4P-SHF-AA) JST
*2
(2) Contacts (BHF-001T-0.8SS)
JST
*6
LNK-048
Remote IO Unit
24-Point Output / 24-Point Input
[Characteristics]
Remote IO can be used in a MPC-68K system equipped with MPCLNK.  LNK-048 is equipped with 24-
point input and 24-point output, and can monitor the status of a sensor distant from the host or control
the actuator.  Also, if used as an IO etc. for a control BOX of an apparatus, because the host and LNK-
048 can be connected via a twisted pair, it will also become a wiring-saving system.
Also, it can be used as a remote IO of a personal computer equipped with MPCLNK or PCLNK (PCM-
95W03, with a case).
[Specification]
Communication: RS-485/SDLC standard 750 kpps.  SN75176B used.
Pulse transformer isolated.
Cable:  Shielded twisted pair to be used (60 nF/km)
Power source:  DC 24V ± 10%
Consumed current:  150 mA
[Accessories]
(1) Power connector (H4P-SHF-AA)
JST
*1
(2) Power connectors (H3P-SHF-AA)
JST
*2
(3) Contacts (BHF-001T-0.8SS)
JST
*10
* MPC-LNK model will be modified due to production discontinuation of its component ICs within coming years.  Although the new
series and old series cannot be combined, they can be used in the same software environment.  Please take note of this.
(3)
(2)
(1)
(1)
(2)
(1)
(2)
MPCLNK
CEP-028C
CEL CORP.
C
A