Datasheet

Development Systems Ordering Guide
DS30177T-page 26 © 2005 Microchip Technology Inc.
CMX-Tiny+™ for dsPIC30F Devices
In some cases, well-structured linear programming is
sufficient for a product. In most cases, however,
programmers appreciate not having to worry about
structuring their code to perform all necessary tasks in
a timely manner. This is where CMX-Tiny+ can help.
CMX-Tiny+ allows tasks (pieces of code that do
specific duties) to run quasi-concurrently. This means
that tasks will seem to run all at the same time – doing
many specific jobs simultaneously.
CMX-Tiny+ takes the worry and headaches out of
real-time programming. The software lets the
embedded programmer concentrate on the overall
application while taking care of the little details.
Finish projects faster and more efficiently with
CMX-Tiny+.
Some RTOS software offers only cooperative
scheduling, which means that the running task has to
call the scheduler to perform a task switch. Others
offer time slicing in which each task runs for a certain
period of time, at which point, a task switch takes
place no matter what. Others claim to be fully
preemptive, yet do not allow any interrupt to cause a
preemption. All of these models will fail at one point or
another.
CMX-Tiny+ allows a task of higher priority that is able
to run (whether starting or resuming) to preempt the
lower priority running task. This will cause the
scheduler to save the context of the running (lower
priority) task and restore the context of the higher
priority task so that it is now running.
A truly preemptive RTOS allows interrupts to cause an
immediate task switch. This means that the interrupts
now have the added ability of using the RTOS’s
functions.
In addition, CMX-Tiny+ has been especially designed
to offer such a small Flash/RAM footprint that it can be
used with only the on-board Flash/RAM of the dsPIC
DSC as a single chip solution. Based upon a scaled
down version of the popular CMX-RTX™, CMX-Tiny+
retains most of the power of CMX-RTX, as well as the
more frequently used functions.
Features
• Extremely small Flash/RAM footprint
• Truly preemptive RTOS
• Low-power mode supported
• Full source code with every purchase
• Free technical support and updates
• Low, economical pricing
• No royalties on shipped products
• Backward compatible with CMX-Scheduler™
• Integrated with CMX-MicroNet™ for optional
networking connectivity
CMX-Tiny+ Specifications for
dsPIC
®
DSC Products
Flash
• All CMX Functions: 2304 bytes
• CMX Initialize Module: 249 bytes
• CMX Assembly Module (scheduler): 570 bytes
• RAM, Each Task Control Block: 13 bytes
• Flash, Each Task Control Block: 6 bytes
• Min. Context Switch:
- 71 cycles (starting a task)
- 121 cycles (resuming a task)
• CMX functions are contained in a library, thus
reducing code size, if not referenced
Ordering Information:
SW300032 CMX-Tiny+™ for dsPIC30F Devices
DS51436
“CMX-Tiny+ ™ for dsPIC30F Product Overview” (Available at: www.microchip.com)