def __init__(self, spi_cs, spi_bus = board.SPI()):
from adafruit_bus_device.spi_device import SPIDevice as spidev
_spi = spidev(spi_bus, spi_cs, baudrate=1000000)
read_buffer = bytearray(1)
# We don't know what state the flash is in, so make sure it's not up to anything, then reset.
with _spi as spi:
while True:
# The write in progress bit should be low.
spi.write(bytearray([SFLASH_CMD_READ_STATUS]))
spi.readinto(read_buffer)
if read_buffer[0] & 0x01 == 0:
break
while True:
# The suspended write/erase bit should be low.
spi.write(bytearray([SFLASH_CMD_READ_STATUS2]))
spi.readinto(read_buffer)
if read_buffer[0] & 0x80 == 0:
break
# reset and disable writes
spi.write(bytearray([SFLASH_CMD_ENABLE_RESET]))
spi.write(bytearray([SFLASH_CMD_RESET]))
spi.write(bytearray([SFLASH_CMD_WRITE_DISABLE]))
self._spi = _spi
super().__init__()
def __init__(self,
spi_bus,
spi_cs,
write_protect=False,
wp_pin=None,
baudrate=100000):
from adafruit_bus_device.spi_device import SPIDevice as spidev
_spi = spidev(spi_bus, spi_cs, baudrate=baudrate)
read_buffer = bytearray(4)
with _spi as spi:
spi.write(bytearray([_SPI_OPCODE_RDID]))
spi.readinto(read_buffer)
prod_id = (read_buffer[3] << 8) + (read_buffer[2])
if (read_buffer[0] != _SPI_MANF_ID) and (prod_id != _SPI_PROD_ID):
raise OSError("FRAM SPI device not found.")
self._spi = _spi
super().__init__(_MAX_SIZE_SPI, write_protect, wp_pin)
def __init__(
self,
spi_bus: SPI,
spi_cs: DigitalInOut,
write_protect: bool = False,
wp_pin: Optional[DigitalInOut] = None,
baudrate: int = 100000,
max_size: int = _MAX_SIZE_SPI,
):
from adafruit_bus_device.spi_device import ( # pylint: disable=import-outside-toplevel
SPIDevice as spidev, )
_spi = spidev(spi_bus, spi_cs, baudrate=baudrate)
read_buffer = bytearray(4)
with _spi as spi:
spi.write(bytearray([_SPI_OPCODE_RDID]))
spi.readinto(read_buffer)
prod_id = (read_buffer[3] << 8) + (read_buffer[2])
if (read_buffer[0] != _SPI_MANF_ID) and (prod_id != _SPI_PROD_ID):
raise OSError("FRAM SPI device not found.")
self._spi = _spi
super().__init__(max_size, write_protect, wp_pin)