Skip to content

fix addressing for larger SPI parts #20

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 2 commits into from
Sep 22, 2020
Merged

fix addressing for larger SPI parts #20

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
ebe73ce
fix for larger devices
jerryneedell Sep 22, 2020
f80c71c
black updates
jerryneedell Sep 22, 2020
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
37 changes: 27 additions & 10 deletions adafruit_fram.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -51,8 +51,8 @@
__version__ = "0.0.0-auto.0"
__repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_FRAM.git"

_MAX_SIZE_I2C = const(32768)
_MAX_SIZE_SPI = const(8192)
_MAX_SIZE_I2C = const(0x8000)
_MAX_SIZE_SPI = const(0x2000)

_I2C_MANF_ID = const(0x0A)
_I2C_PROD_ID = const(0x510)
Expand Down Expand Up @@ -310,7 +310,13 @@ class FRAM_SPI(FRAM):

# pylint: disable=too-many-arguments,too-many-locals
def __init__(
self, spi_bus, spi_cs, write_protect=False, wp_pin=None, baudrate=100000
self,
spi_bus,
spi_cs,
write_protect=False,
wp_pin=None,
baudrate=100000,
max_size=_MAX_SIZE_SPI,
):
from adafruit_bus_device.spi_device import ( # pylint: disable=import-outside-toplevel
SPIDevice as spidev,
Expand All @@ -327,20 +333,26 @@ def __init__(
raise OSError("FRAM SPI device not found.")

self._spi = _spi
super().__init__(_MAX_SIZE_SPI, write_protect, wp_pin)
super().__init__(max_size, write_protect, wp_pin)

def _read_address(self, address, read_buffer):
write_buffer = bytearray(3)
write_buffer = bytearray(4)
write_buffer[0] = _SPI_OPCODE_READ
write_buffer[1] = address >> 8
write_buffer[2] = address & 0xFF
if self._max_size > 0xFFFF:
write_buffer[1] = (address >> 16) & 0xFF
write_buffer[2] = (address >> 8) & 0xFF
write_buffer[3] = address & 0xFF
else:
write_buffer[1] = (address >> 8) & 0xFF
write_buffer[2] = address & 0xFF

with self._spi as spi:
spi.write(write_buffer)
spi.readinto(read_buffer)
return read_buffer

def _write(self, start_address, data, wraparound=False):
buffer = bytearray(3)
buffer = bytearray(4)
if not isinstance(data, int):
data_length = len(data)
else:
Expand All @@ -359,8 +371,13 @@ def _write(self, start_address, data, wraparound=False):
spi.write(bytearray([_SPI_OPCODE_WREN]))
with self._spi as spi:
buffer[0] = _SPI_OPCODE_WRITE
buffer[1] = start_address >> 8
buffer[2] = start_address & 0xFF
if self._max_size > 0xFFFF:
buffer[1] = (start_address >> 16) & 0xFF
buffer[2] = (start_address >> 8) & 0xFF
buffer[3] = start_address & 0xFF
else:
buffer[1] = (start_address >> 8) & 0xFF
buffer[2] = start_address & 0xFF
spi.write(buffer)
for i in range(0, data_length):
spi.write(bytearray([data[i]]))
Expand Down