QDK PIC24/dsPIC-C30 - Quantum Leaps

QDK
PIC24/dsPIC-C30
www.state-machine.com/pic
(3) QK_ISR_EXIT(); /* inform QK about exiting the ISR */
}
(1) The macro QK_ISR() is used before the ISR signature. Here the PSV control is set to no_auto_ps,
which avoids saving and restoring the PSVPAG register. If your ISR body references const variables
or string literals using the constants-in-code memory model, you need to define this argument to
auto_psv.
(2) When software tracing is enabled, the ISR updates the 32-bit time stamp at tick, which is used to
provide a 32-bit time stamp for the trace events.
(3) The macro QK_ISR_EXIT() is invoked at the end of every ISR to perform the asynchronous context
switch, if necessary.
4.2.1 Explanation of ISR code for the preemptive QK kernel
Listing 9 shows the disassembled code for the _T2Interrupt ISR from Listing 8. The highlighted code is
generated by the macros QK_ISR() and QK_ISR_EXIT(). The explanation section immediately following
the listing clarifies the most important points.
Listing 9: Disassembled code for T2Interrupt ISR
72: QK_ISR(no_auto_psv) _T2Interrupt() {
(1) 009F8 F80036 push.w 0x0036
(2) 009FA BE9F80 mov.d 0x0000,[0x001e++]
(3) 009FC 97B84F mov.w [0x001e-8],0x0000
(4) 009FE DE00CD lsr 0x0000,#13,0x0002
(5) 00A00 200010 mov.w #0x1,0x0000
(6) 00A02 DD0001 sl 0x0000,0x0002,0x0000
(7) 00A04 B76993 ior.b 0x0993
(8) 00A06 370002 bra 0x000a0c
(9) 00A08 F80036 push.w 0x0036
(10) 00A0A BE9F80 mov.d 0x0000,[0x001e++]
(11) 00A0C BE9F82 mov.d 0x0004,[0x001e++]
(12) 00A0E BE9F84 mov.d 0x0008,[0x001e++]
(13) 00A10 BE9F86 mov.d 0x000c,[0x001e++]
(14) 00A12 781F88 mov.w 0x0010,[0x001e++]
73: _T2IF = 0; /* clear Timer 2 interrupt flag */
00A14 A9E084 bclr.b 0x0084,#7
74:
75: #ifdef Q_SPY
76: l_tickTime += BSP_TMR2_PERIOD; /* TMR2 overflow */
77: #endif
78:
79: QF_tick(); /* handle all armed time events in QF */
00A16 07027E rcall 0x000f14
80:
81: QK_ISR_EXIT(); /* inform QK about exiting the ISR */
(15) 00A18 800218 mov.w 0x0042,0x0010
(16) 00A1A DE4045 lsr 0x0010,#5,0x0000
(17) 00A1C 600067 and.w 0x0000,#7,0x0000
(18) 00A1E 200011 mov.w #0x1,0x0002
(19) 00A20 DD0800 sl 0x0002,0x0000,0x0000
(20) 00A22 B34010 ior.b #0x1,0x0000
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