OsError when booting m4 from m7 micropython

Official Hardware Mega GIGA R1 WiFi
1

I have been trying to get the m7 working with the m4. With the m7 having micropython. This is my main.py for the m7:

import msgpackrpc

# Create a MsgPackRPC object.
rpc = msgpackrpc.MsgPackRPC()
# Start the remote processor and wait for it to be ready to communicate.
rpc.start(firmware=0x08180000)

When I run this script. The built in led alternates between green and red a couple of times then stops and raises

Traceback (most recent call last):
  File "<stdin>", line 6, in <module>
  File "msgpackrpc.py", line 185, in start
OSError: timeout waiting for the remote processor to start

I have the m4 running the blink example.

2

This was fixed by changing firmware to 0x008100000