I have a coroutine which wait for an event to be set :
@cocotb.coroutine
def wb_RXDR_read(self):
""" waiting util RXDR is read """
if not self._RXDR_read_flag:
while True:
yield self._RXDR_read_event.wait()
break
I want to «yield» on it with a timeout. Then to do that I did this :
RXDR_timeout = Timer(250, units="us")
ret = yield [RXDR_timeout, self.wb_RXDR_read()]
if ret == RXDR_timeout:
self._dut._log.error("Timeout on waiting RXDR to be read")
raise TestError()
But I get this error :
2ns ERROR Coroutine i2c_write yielded something the scheduler can't handle
Got type: <type 'list'> repr: [<cocotb.triggers.Timer object at 0x7f2098cb1350>, <cocotb.decorators.RunningCoroutine object at 0x7f2098cb1610>] str: [<cocotb.triggers.Timer object at 0x7f2098cb1350>, <cocotb.decorators.RunningCoroutine object at 0x7f2098cb1610>]
Did you forget to decorate with @cocotb.coroutine?
My coroutine is decorated with @cocotb.coroutine. If I yield it alone that works :
yield self.wb_RXDR_read() # <- that works
But I can't put it in a list. Is it possible to put coroutine in a list to block like unix select() ? Or is it reserved to Trigger class ?
Ok I found the solution. In fact Coroutine can't be triggered in select like fashion itself. It should be started as a thread first, and to detect the end of the coroutine the .join()
method must be put in the yield list:
RXDR_timeout = Timer(250, units="us")
RXDR_readth = cocotb.fork(self.wb_RXDR_read())
ret = yield [RXDR_timeout, RXDR_readth.join()]
if ret == RXDR_timeout:
self._dut._log.error("Timeout on waiting RXDR to be read")
raise TestError()
The thing to remember is :
fork()
and join()