Product Overview
The Omron 3G8F5-CLK01 is the ISA-bus Controller Link Support Board — the PC/host-side interface card that lets an IBM PC/AT (or compatible) industrial computer join an Omron Controller Link token-ring network as a full peer node alongside CS1, CJ1, C200Hα, CVM1/CV-series PLCs. It is the “PC half” of the 3G8F5-CLK21-E wired-system kit (the “-E” kit bundles one 3G8F5-CLK01 board + 3.5″ floppy with Controller Link Support Software + Operation Manual W307 + comms connector; the optical sibling is 3G8F5-CLK11-E kit bundling 3G8F5-CLK02 for the PC side). Do not confuse the Omron 3G8F5-CLK01 with the PLC-mounted CJ1W-CLK23 or CS1W-CLK23 — those are the PLC-side Controller Link units; the 3G8F5-CLK01 lives in a PC ISA slot, not a PLC backplane.
Functionally, the Omron 3G8F5-CLK01 implements the Controller Link physical and data-link layer on the PC side: it attaches to the shielded-twisted-pair (STP, VCTF class, 500 m max) or — when paired with the optical kit — H-PCF/GI fibre (up to 20 km with repeaters) Controller Link medium, participates in the token-pass arbitration, and presents a shared-data-area (max 62,000 words send/receive when the peer is a PC-node, per Omron W370) that the PC application can read/write via the Controller Link BIOS → Driver → MS-C library (CLKMSC.LIB) stack. This lets a SCADA or custom-C application on the PC exchange process data, issue FINS commands (SEND/RECV/CMND), and pull RAS error logs from any node on the ring — all without a protocol gateway.
The Omron 3G8F5-CLK01 is built on a 106.7 × 163 mm ISA full-length form factor, draws ≤0.4 A @ 5 VDC from the PC PSU (no separate 24 V except when backup-power for node-bypass is used — that 24 V DC feeds the CLK unit/board backup input, not the ISA core), and runs under IBM PC DOS 7.0 / MS DOS 6.2 with i386+ CPU. The software stack shipped on the 3.5″ floppy includes Controller Link BIOS (resident TSR), CLK Driver, and the MS-C large-model library (CLKMSC.LIB, A-model) so OEMs could build DOS-hosted FINS applications in C. Later Windows-hosted wrappers (CX-Server, Kepware OMRON FINS Ethernet/CLK drivers) can also ride the same board if the OS still has the 16-bit BIOS shim, but the is fundamentally a DOS/early-Win9x-era card — hence its “legacy A-class” status today.
Positioning-wise, the was Omron’s answer to “how does a PC sit on the same deterministic token-ring as my CV/CS1 PLCs without going through a gateway?” — useful in late-90s to mid-2000s FA cells: automotive weld lines (20+ PLCs + 1 SCADA PC), paper conversion lines, tire-building cells, and any legacy C200H/CV/CS1 plant where the original ISA-hosted SCADA is still alive on an Advantech/Siemens rackmount PC running DOS or Win98. The card supports bypass-node behaviour (via optional 24 V DC backup supply to the CLK PCB) so that if the PC powers off or the ISA card faults, the token ring stays up — the rest of the PLC nodes keep their data link. This is a subtle but critical resilience feature that pure-USB or PCIe-bridge substitutes can’t replicate without an active emulation layer.
Technical Specifications
| Parameter | Value |
|---|---|
| Product Model | |
| Manufacturer | Omron Corporation (Japan) |
| Product Type | Controller Link Support Board (PC/AT ISA-bus host card) |
| Bus Interface | ISA 16-bit (IBM PC/AT compatible), full-length |
| Corresponding Kit (wired) | 3G8F5-CLK21-E (bundles + 3.5″ floppy + manual + connector) |
| Corresponding Kit (optical) | 3G8F5-CLK11-E (bundles 3G8F5-CLK02 PC card; is wired-only) |
| Supply Voltage | +5 VDC from PC PSU (ISA bus rail) |
| Current Consumption | ≤ 0.4 A @ 5 VDC (max) |
| Backup Power Input | 24 V DC (external, for node-bypass function only, not board core) |
| Communication Rate | 2 Mbps (fixed, Controller Link token-ring) |
| Max Nodes / Ring | 32 (including PC node) |
| Topology | Bus or Star (star requires repeater/hub) |
| Media (wired) | Shielded twisted-pair (VCTF), 500 m max (no repeater) |
| Media (optical, via CLK11-E kit) | H-PCF / GI fibre, up to 20 km (with 3G8F5-CRT repeaters) |
| Data Link Capacity (PC node) | Send + receive up to 62,000 words (per Omron W370 for PCI/ISA PC nodes) |
| Protocol | Omron Controller Link / FINS (token-pass) |
| Supported OS (official) | IBM PC DOS 7.0 / MS DOS 6.2 |
| Supported CPU (official) | i386 or higher |
| Supported Compiler / Lib | Microsoft C 7.0A (large model), CLKMSC.LIB |
| Software Stack | Controller Link BIOS (TSR) → CLK Driver → Application Library |
| Dimensions (W × L) | 106.7 × 163 mm |
| Weight | ≈ 160 g (excluding bracket) |
| Operating Temp. | +5 to +45 °C |
| Storage Temp. | –20 to +60 °C |
| Humidity | 8%–80% RH, non-condensing |
| Atmosphere | Free of corrosive gases (ISA/FA grade) |
| Indicators | Run / Err / Send / Recv (front bracket LEDs, model-dependent) |
| Certifications | CE, UL, cUL, KC (per CLK family) |
| Companion Cards | 3G8F5-CLK02 (optical PC board), 3G8F5-CLK51/52 (later PCI variants) |
Main Features and Advantages
ISA-bus PC node on deterministic token-ring:
The core proposition of the is letting a DOS/Win9x industrial PC sit as a native node on the same 2 Mbps token-pass Controller Link that the CS1/CJ1/CVM1 PLCs share. Unlike Ethernet (CSMA/CD, non-deterministic), Controller Link guarantees each node a transmit window per token rotation — the PC node gets the same determinism as PLC nodes, which matters when the PC is doing soft-real-time things like vision-triggered reject, SPC data harvest, or multi-robot coordination where the PC issues FINS CMNDs to individual PLC stations on the ring.
62,000-word data-link window:
Per Omron W370 (), a “Personal computer with PCI/ISA Board” Controller Link node can send/receive up to 62,000 words — far larger than the 1,000–4,000 words typical of PLC-side units (CS1W-CLK13 = 4,000 send/receive; pre-V1.2 CS = 12,000; CVM1 = 8,000). The inherits this PC-node capacity: a SCADA PC can mirror near-complete process images from every PLC on the ring into its shared memory without chopping into multiple SEND/RECV cycles. For a 20-PLC body-shop weld line, that means one PC can hold the entire cell’s tag set in one cyclical data-link refresh.
Bypass-node with 24 V backup:
If the PC hosting the loses power (PSU trip, planned shutdown, BSOD reboot), the ring doesn’t collapse — the CLK PCB’s backup 24 V DC input (fed from the same 24 V aux that feeds PLC-side CLK units) keeps the transceiver alive in bypass mode, and the token simply skips the PC node until it rejoins. This is why legacy lines can keep the original ISA-SCADA alive for decades — the PC is non-critical-path to the PLC-PLC data link; it just sips the shared memory.