Each SoC family has its own clocks and timings/timeouts. For I2C, the
default source clock is either APB (ESP32, ESP32-S2) or XTAL (ESP32-S3,
ESP32-C3) as shown in the datasheets. Since
machine_i2c.c/machine_hw_i2c_init() uses the default clk_flags (0), the
alternate low-power clock source is never selected in ESP-IDF
i2c.c/i2c_param_config(). There is not an API in i2c.c to get the source
clock frequency, so a compile-time value is used based on SoC family.
Also, the maximum timeout is different across the SoC families, so use the
I2C_LL_MAX_TIMEOUT constant to eliminate the warning from
i2c_set_timeout().
With these changes, the following results were obtained. The I2C SCL
frequencies were measured with a Saleae logic analyzer.
ESP32 (TTGO T Dislay)
I2C(0, scl=22, sda=21, freq=101781) Measured: 100KHz
I2C(0, scl=22, sda=21, freq=430107) Measured: 400KHz
I2C(0, scl=22, sda=21, freq=1212121) Measured: 941KHz
ESP32-S3 (TTGO T-QT)
I2C(0, scl=34, sda=33, freq=111111) Measured: 107KHz
I2C(0, scl=34, sda=33, freq=444444) Measured: 400KHz
I2C(0, scl=34, sda=33, freq=1111111) Measured: 842KHz
ESP32-C3 (XIAO ESP32C3)
I2C(0, scl=7, sda=6, freq=107816) Measured: 103KHz
I2C(0, scl=7, sda=6, freq=444444) Measured: 380KHz
I2C(0, scl=7, sda=6, freq=1176470) Measured: 800KHz
(ESP32-S2 board was not available for testing.)
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>
When MICROPY_PY_MACHINE_I2C_TRANSFER_WRITE1 is enabled the port's hardware
I2C transfer functions should support the MP_MACHINE_I2C_FLAG_WRITE1
option, but software I2C will not. So add a flag to the I2C protocol
struct so each individual protocol can indicate whether it supports this
option or not.
Fixes issue #8765.
Signed-off-by: Damien George <damien@micropython.org>
I2C transfers are much more efficient if they are combined, instead of
doing separate writes and reads.
Fixes issue #7134.
Signed-off-by: Damien George <damien@micropython.org>
Hardware I2C implementations must provide a .init() protocol method if they
want to support reconfiguration. Otherwise the default is that i2c.init()
raises an OSError (currently the case for all ports).
mp_machine_soft_i2c_locals_dict is renamed to mp_machine_i2c_locals_dict to
match the generic SPI bindings.
Fixes issue #6623 (where calling .init() on a HW I2C would crash).
Signed-off-by: Damien George <damien@micropython.org>
With a warning that this way of constructing software I2C/SPI is
deprecated. The check and warning will be removed in a future release.
This should help existing code to migrate to the new SoftI2C/SoftSPI types.
Signed-off-by: Damien George <damien@micropython.org>
Previous commits removed the ability for one I2C/SPI constructor to
construct both software- or hardware-based peripheral instances. Such
construction is now split to explicit soft and non-soft types.
This commit makes both types available in all ports that previously could
create both software and hardware peripherals: machine.I2C and machine.SPI
construct hardware instances, while machine.SoftI2C and machine.SoftSPI
create software instances.
This is a breaking change for use of software-based I2C and SPI. Code that
constructed I2C/SPI peripherals in the following way will need to be
changed:
machine.I2C(-1, ...) -> machine.SoftI2C(...)
machine.I2C(scl=scl, sda=sda) -> machine.SoftI2C(scl=scl, sda=sda)
machine.SPI(-1, ...) -> machine.SoftSPI(...)
machine.SPI(sck=sck, mosi=mosi, miso=miso)
-> machine.SoftSPI(sck=sck, mosi=mosi, miso=miso)
Code which uses machine.I2C and machine.SPI classes to access hardware
peripherals does not need to change.
Signed-off-by: Damien George <damien@micropython.org>
Mark Grosen
iabdalkader
Jim Mussared
Damien George
Mike Causer
Damien George