i = 0
pio.pin.setdir(pio.OUTPUT,pio.PA_0)
pio.pin.setpull( pio.PULLDOWN,pio.PA_0)
local prev_gpio
-- This is the GPIO interrupt on change (falling edge) interrupt
local function gpio_posedge_handler( resnum )
local port, pin = pio.decode( resnum )
print( string.format( "GPIO POSEDGE interrupt on port %d, pin %d", port, pin ) )
if prev_gpio then prev_gpio( resnum ) end
end
-- Set GPIO interrupt on change (negative edge) interrupt handler
prev_gpio = cpu.set_int_handler( cpu.INT_GPIO_POSEDGE, gpio_posedge_handler )
-- Enable GPIO interrupt on change (negative edge) for pin 0 of port 0
cpu.sei( cpu.INT_GPIO_POSEDGE, pio.PA_0)
while uart.getchar( 0, 0 ) == "" do
end
-- Cleanup
-- Disable the GPIO interrupt on change (negative edge) interrupt
cpu.cli( cpu.INT_GPIO_POSEDGE, keypin)
-- Clear the GPIO interrupt handler
cpu.set_int_handler( cpu.INT_GPIO_POSEDGE, nil );
例子二：定时器中断
local vtmrid = tmr.VIRT0
local to = 1500000
local prev_tmr, new_prev_tmr
-- This is the timer interrupt handler
local function tmr_handler( resnum )
print( string.format( "Timer interrupt for id %d", resnum ) )
if prev_tmr then prev_tmr( resnum ) end
end
-- This is the timer interrupt handler that gets set after tmr_handler
local function new_tmr_handler( resnum )
print( string.format( "NEW HANDLER: timer interrupt for id %d", resnum ) )
-- This will chain to the previous interrupt handler (tmr_handler above)
if new_prev_tmr then new_prev_tmr( resnum ) end
end
-- Set timer interrupt handler
prev_tmr = cpu.set_int_handler( cpu.INT_TMR_MATCH, tmr_handler )
-- Setup periodic timer interrupt for virtual timer 0
tmr.set_match_int( vtmrid, to, tmr.INT_CYCLIC )
-- Enable timer match interrupt on virtual timer 0
cpu.sei( cpu.INT_TMR_MATCH, vtmrid )
local tmrid, count = 0, 0
while uart.getchar( 0, 0 ) == "" do
print "Outside interrupt"
for i = 1, 1000 do tmr.delay( tmrid, 1000 ) end
count = count + 1
if count == 5 then
print "Changing timer interrupt handler"
new_prev_tmr = cpu.set_int_handler( cpu.INT_TMR_MATCH, new_tmr_handler )
end
end
-- Cleanup
-- Stop the timer from generating periodic interrupts
tmr.set_match_int( vtmrid, 0, tmr.INT_CYCLIC );
-- Disable the timer interrupt on match interrupt
cpu.cli( cpu.INT_TMR_MATCH, vtmrid )
-- Clear the timer interrupt handler
cpu.set_int_handler( cpu.INT_TMR_MATCH, nil );