M227 Programmable Clock/Counter/Timer M-Module

The newest module in our quiver of M-modules is the M227 Programmable Clock/Counter/Timer M-Module. Newly released, this module is extremely flexible and, thus, provides a large number of possible timing functions. The module has three 32-bit counters capable of running up to 50MHz, two programmable front panel inputs, three programmable front panel outputs and two backplane trigger lines.

The inputs can be used to synchronize and control the three 32-bit counters. The inputs can start/stop a counter, gate a counter, clock a counter, latch a counter value, and reset a counter. The two inputs and the two backplane triggers can be routed to any of the three counters and the two front panel inputs have a programmable threshold, level sensitivity and input impedance.

The outputs can be configured to be any of the various clocks running onboard the M227, a counter carry signal, or counter match signal. It is also possible to route the outputs to an input of one or more of the counters so that the counters can be daisy chained or so that the state of one counter can control the state of another counter. The four divider networks, the clock prescaler and the three counters allow the M227 to generate clock/timing signals of just about any frequency up to 50MHz.

In addition to the high level of flexibility in the counters and the I/O, the M227 has clock disciplining logic that allows it to discipline it's internal clock to a highly accurate clock such as from an ovenized oscillator like the M207 or to the 1PPS/100PPS signal of a GPS timing module like the M213.

It is impossible to imagine all the possible functions that can be created with the M227. It's flexibility makes it a great solution to most standard counter/timer application as well as to many applications where the counter/timer function is less ordinary. Hopefully the brief description in this article helps you wrap your mind around the possibilities.

On a side note, the M227 was designed to include all the same functionality of the VX491C Counter/Timer VXI module. Two M227's on a VXI carrier can replace one VX491C, leaving room for other functionality (up to 4 more M-Modules) in the same VXI slot. Or the functionality can be moved to a different platform such as PXI and LXI.