Speed Link (HSL) is an innovative distributed I/O technology designed
for automation applications requirement. HSL is based on an open
standard, RS-422, which is designed for full/half-duplex, multi-drop
serial transmission. The network employs standard CAT 5 cable for
point-to-point connections between its major components and CRC-12
for error-correction. Sensors and controls at I/O points connect
to the system through simple copper wires. In addition, I/O modules
are hot swappable, thereby replacing failed modules in the field
without having to power down the system. Since RS-422 operates through
polling, data collisions are not a factor and message overhead is
extremely low. HSL uses a 6Mbps transmission speeds and can scan
1000 I/O points per millisecond. Maximum scan rates of less than
2 milliseconds are sustained for 2,000 to 32,000 I/O points. A series
of real-time I/O networking products including PCI-bus master cards
and slave I/O modules up to 200m away from the PC. The slave units
can be placed near the I/O points being monitored or controlled,
reducing wire runs and minimizing potential noise and signal losses.
For those who are seeking for the optimal solution for speedy, easy
distributed I/O, HSL is definitely your best solution.
The master ASIC controller fully utilizes the 6Mbps transmission
speed running on full/half-duplex RS-422. All the command response
protocols are handling by the ASIC itself with full speed polling
time period for a HSL master to scan all
slave I/O modules is deterministic. It is exactly
proportional to the number of slave address
ID. For a HSL system with 30 slave I/O
modules, the scanning time period is precisely
30 x 30.1?s = 0.903ms.
The connection among the HSL master and all slave I/O modules requires
merely the commercial Ethernet cables, which
dramatically reduce the wiring effort. With just Ethernet cables,
hundreds even thousands of I/O data can be transmitted between
the HSL master and slave I/O modules. This is absolutely the easiest
and most cost eff ective wiring solution.
There are at most 63 slave I/O modules in one
HSL master, and there are at most 16 HSL
master supported in one computer system (8
pieces of PCI-7852). That is, 63 x 16 = 1008
modules. Just choose all modules as HSLDI16DO16-
DB-NN, and the total number of
I/O points is 16,128 DI and 16,128 DO.
I/O points of add-on card needs not only the card itself but also
a free PCI or ISA slot. What you need to do for HSL now
is select the I/O type and module number by easy serial wiring,
Clips an Ethernet cable with RJ45 between modules and master
then everything is done.