STM32F0 has PCLK=48MHz and maximum ADC clock is 14MHz so use PCLK/4=12MHz
to stay within spec of the ADC peripheral. In pyb.ADC set common sampling
time to approx 4uS for internal and external sources. In machine.ADC
reduce sample time to approx 1uS for external source, leave internal at
maximum sampling time.
This commit adds the option to use HSE or MSI system clock, and LSE or LSI
RTC clock, on L4 MCUs.
Note that prior to this commit the default clocks on an L4 part were MSI
and LSE. The defaults are now MSI and LSI.
In mpconfigboard.h select the clock source via:
#define MICROPY_HW_RTC_USE_LSE (0) or (1)
#define MICROPY_HW_CLK_USE_HSE (0) or (1)
and the PLLSAI1 N,P,Q,R settings:
#define MICROPY_HW_CLK_PLLSAIN (12)
#define MICROPY_HW_CLK_PLLSAIP (RCC_PLLP_DIV7)
#define MICROPY_HW_CLK_PLLSAIQ (RCC_PLLQ_DIV2)
#define MICROPY_HW_CLK_PLLSAIR (RCC_PLLR_DIV2)
For use with F0 MCUs that don't have HSI48. Select the clock source
explicitly in mpconfigboard.h.
On the NUCLEO_F091RC board use HSE bypass when HSE is chosen because the
NUCLEO clock source is STLINK not a crystal.
Before this patch the UART baudrate on F0 MCUs was wrong because the
stm32lib SystemCoreClockUpdate sets SystemCoreClock to 8MHz instead of
48MHz if HSI48 is routed directly to SYSCLK.
The workaround is to use HSI48 -> PREDIV (/2) -> PLL (*2) -> SYSCLK.
Fixes issue #5049.
Enabled by default, but disabled when REPL is connected to the VCP (this is
the existing behaviour). Can be configured at run-time with, eg:
pyb.USB_VCP().init(flow=pyb.USB_VCP.RTS | pyb.USB_VCP.CTS)
The new fdcan.c file provides the low-level C interface to the FDCAN
peripheral, and pyb_can.c is updated to support both traditional CAN and
FDCAN, depending on the MCU being compiled for.
According to the schematic, the SDRAM part on this board is a
MT48LC4M32B2B5-6A, with "Row addressing 4K A[11:0]" (per datasheet). This
commit updates mpconfigboard.h from 13 to 12 to match.
- STM32F407VGT6 (1MB of Flash, 192+4 Kbytes of SRAM)
- 5V (via USB) or Li-Polymer Battery (3.7V) power input
- 2 x LEDs
- 2 x user switches
- 2 x mikroBUS sockets
- 2 x 1x26 mikromedia-compatible headers (52 pins)
https://www.mikroe.com/clicker-2-stm32f4
Mboot currently requires at least three LEDs to display each of the four
states. However, since there are only four possible states, the states can
be displayed via binary counting on only 2 LEDs (if only 2 are available).
The existing patterns are still used for 3 or 4 LEDs.
As per PEP 485, this function appeared in for Python 3.5. Configured via
MICROPY_PY_MATH_ISCLOSE which is disabled by default, but enabled for the
ports which already have MICROPY_PY_MATH_SPECIAL_FUNCTIONS enabled.
Before this patch I2C transactions using a hardware I2C peripheral on F0/F7
MCUs would not correctly generate the I2C restart condition, and instead
would generate a stop followed by a start. This is because the CR2 AUTOEND
bit was being set before CR2 START when the peripheral already had the I2C
bus from a previous transaction that did not generate a stop.
As a consequence all combined transactions, eg read-then-write for an I2C
memory transfer, generated a stop condition after the first transaction and
didn't generate a stop at the very end (but still released the bus). Some
I2C devices require a repeated start to function correctly.
This patch fixes this by making sure the CR2 AUTOEND bit is set after the
start condition and slave address have been fully transferred out.
Some SD/MMC breakout boards don't support 4-bit bus mode. This adds a new
macro MICROPY_HW_SDMMC_BUS_WIDTH that allows each board to define the width
of the SD/MMC bus interface used on that board, defaulting to 4 bits.
