QDK PIC24/dsPIC-XC16 - Quantum Leaps

QDK
PIC24/dsPIC-XC16
www.state-machine.com/pic
XC18 compiler, although the preemptive version requires special macros to be invoked upon entering and
exiting ISRs.
The interrupt locking policy is implemented very efficiently by means of the DISI instruction (see
Section 3.2). As described in Section 8.2.3 of “PIC24F Family Reference Manual” [PIC24 Ref], “The DISI
instruction only disables interrupts with priority levels 1-6. Priority level 7 interrupts and all trap events still
have the ability to interrupt the CPU when the DISI instruction is active.” This means that interrupts with
IPL of 7 are never disabled and thus run with “zero interrupt latency”.
NOTE: Obviously, true “zero interrupt latency” is technically impossible. The term means here that
the NMI-level interrupt(s) execute with the minimal latency achievable in PIC24/dsPIC hardware and
that no additional latency is added to the NMI-level interrupt(s) because of interrupt locking in QP.
The use of NMI to achieve “zero interrupt latency” is explained in Section 5.
1.5 What’s Included in the QDK-PIC24-dsPIC
This QDK provides the QP port for PIC24 and dsPIC MCUs and two versions of the Dining Philosopher
Problem (DPP) example for each processor (with the cooperative “vanilla” kernel and the preemptive QK
kernel). The actual devices used for testing were: PIC24FJ64GB002 (PIC24) and dsPIC33FJ128MC
(dsPIC).
1.6 Licensing QP
The Generally Available (GA) distribution of QP available for download from the www.statemachine.com/downloads
website is offered with the following two licensing options:
The GNU General Public License version 2 (GPL) as published by the Free
Software Foundation and appearing in the file GPL.TXT included in the packaging of
every Quantum Leaps software distribution. The GPL open source license allows
you to use the software at no charge under the condition that if you redistribute the
original software or applications derived from it, the complete source code for your
application must be also available under the conditions of the GPL (GPL Section
2[b]).
One of several Quantum Leaps commercial licenses, which are designed for
customers who wish to retain the proprietary status of their code and therefore cannot
use the GNU General Public License. The customers who license Quantum Leaps
software under the commercial licenses do not use the software under the GPL and
therefore are not subject to any of its terms.
For more information, please visit the licensing section of our website at: www.statemachine.com/licensing.
1.7 Licensing QM
The QM graphical modeling tool available for download from the www.statemachine.com/downloads
website is free to use, but is not open source. During the
installation you will need to accept a basic End-User License Agreement (EULA),
which legally protects Quantum Leaps from any warranty claims, prohibits removing
any copyright notices from QM, selling it, and creating similar competitive products.
Copyright © Quantum Leaps, LLC. All Rights Reserved.
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