This commit adds support for the `timeout` keyword argument to machine.I2C
on the rp2 port, following how it's done on other ports.
The main motivation here is avoid the interpreter crashing due to infinite
loops when SDA is stuck low, which is quite common if the board gets reset
while reading from an I2C device.
A default timeout of 50ms is chosen because it's consistent with:
- Commit a707fe50b0 which used a timeout of
50,000us for zero-length writes on the rp2 port.
- The machine.SoftI2C class which uses 50,000us as the default timeout.
- The stm32 port's hardware I2C, which uses 50,000us for
I2C_POLL_DEFAULT_TIMEOUT_US.
This commit also fixes the default timeout on the esp32 port to be
consistent with the above, and updates the documentation for machine.I2C to
document this keyword argument.
Instead of being an explicit field, it's now a slot like all the other
methods.
This is a marginal code size improvement because most types have a make_new
(100/138 on PYBV11), however it improves consistency in how types are
declared, removing the special case for make_new.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
The RP2040 I2C hardware can do writes of length 1 and 2, just not of length
0. So only use software I2C for writes of length 0, to improve
performance.
Also increase the software I2C timeout for zero-length writes to
accommodate the behaviour of a wider range of I2C devices.
Fixes issue #8167.
Signed-off-by: Damien George <damien@micropython.org>
This commit adds a new port "rp2" which targets the new Raspberry Pi RP2040
microcontroller.
The build system uses pure cmake (with a small Makefile wrapper for
convenience). The USB driver is TinyUSB, and there is a machine module
with most of the standard classes implemented. Some examples are provided
in the examples/rp2/ directory.
Work done in collaboration with Graham Sanderson.
Signed-off-by: Damien George <damien@micropython.org>
