how to identify a board is connected to a deepsleep shield

[philwilkinson]

I have several LoPy and LoPy4 boards.
Usually I connect LoPy to a deepsleep shield, but not always.
If I use the following code, I will always invoke the deepsleep library's go_to_sleep method to a LoPy, even if it is not connected to a deepsleep shield. The board will not wake from deepsleep in this case.
Some deepsleep methods raise exceptions when called if there is no deepsleep shield attached (e.g. get_wake_status) however go_to_sleep does not.

does anyone know how to check if a board is connected to a deepsleep shield before choosing how to put it into deepsleep?

def sleep_to_next_time(sleep_time=interval):
    t=uos.uname()
    if t[0] == 'LoPy':
        ds = deepsleep.DeepSleep()
        ds.go_to_sleep(sleep_time/1000)
    else:
        machine.deepsleep(sleep_time)

Some deepsleep methods raise exceptions when called e.g. get_wake_status however go_to_sleep does not.

[philwilkinson]

thanks for the response @jcaron. Unfortunately all the methods you suggest only work on the expansion board types, not the deepsleep shield.
The only way I can see to do this is to use an exception handler. Not very pythonic, but it does work.

import deepsleep
ds = deepsleep.DeepSleep()

try:
    ds.get_wake_status()
    shield = True
except:
    shield = False
print(shield)

[jcaron]

@philwilkinson read_hw_version, read_fw_version and read_product_id would probably be good starting points.