Encoders and Counters
Three 24-bit up/down counter pairs may be configured for six incremental encoders, each having 24-bits of resolution. Each channel accepts two phased TTL or RS-422 signals plus an index signal to track encoder direction and displacement. Each input is conditioned and synchronized to the 626’s internal clock.

Unlike conventional counters, the 626’s counters do not accumulate errors when the encoder dithers or changes direction. The 626 supplies 5 volt power to each encoder channel. All counters are programmable and may optionally generate interrupts.

The counter channels have a battery backup feature that keeps them running during a power failure. The 626’s battery charger will recharge an external 3.6V NiCd when power is restored. 

Each counter may be programmed to function as a timer using the 626’s internal clock or an external clock. When paired,  48-bit counters may be used for frequency measurement.

A/D
Sixteen differential input channels are multiplexed to a sample/hold and successive approximation A/D. Each channel may be programmed for ± 5V or  ± 10V. No trim adjustments are needed.

D/A
Four voltage outputs may be programmed for ± 10 volts. A unique circuit prevents unpredictable D/A outputs during CPU initialization. All outputs are reset to zero volts whenever a bus reset occurs.

Watchdog
The 626’s watchdog timer may be connected to the bus reset via a 2-pin connector. It may be enabled or disabled under program control. The timer is automatically disabled whenever a bus reset occurs.

E-stop Relay
An external emergency stop signal may be passed through a mechanical relay on the 626. This E-stop relay may be optionally activated by the 626’s watchdog timer or by other programmed conditions.

Fail-safe Digital I/O
In the event that power is lost to the PC, solid state relays connected to the 626’s digital I/O will not be powered to the on state.  This allows solid state relay boards, such as model 720RBDIN to be powered from a remote power supply without the chance of output relays turning on when the PC is turned off.

Digital I/O
The model 626’s forty-eight digital lines have standard pin outs for solid state relay boards. Each line is software programmable as an input or output. Forty inputs may be programmed for edge detection and interrupts. The status of output lines may be monitored by software. Whenever a system reset occurs, all output channels are turned off.

Software & Manuals
All the features of model 626 may be exercised using software development kit, SDK626.  This 32-bit DLL for Windows 98/NT/2000/XP allows the use of multiple 626 boards. QNX driver and Linux available.

626 Instruction Manual | Released 1/28/04
SDK626 |  Released  4/20/05
626 Linux SDK   | 1/2/07
626 Controls (Active-X, VCL & CLX) |  7/2/02
626 QNX | 4/18/05

Mecahincal Drawings and Images

Quadrature encoders
Dimensions