Allocate per-instance data for drivers from the heap
rather than as static variables from the .data segment.
This converts > 800 bytes of RAM from being always consumed
as static data into being allocated from the heap only when
a particular feature is enabled in the hwsettings object.
A minimal config (no receivers, flexi port disabled, main port
disabled) leaves 2448 bytes of free heap. That's our new baseline.
Approximate RAM (heap) costs of enabling various features:
+ 632 Serial Telemetry (includes 400 bytes of Rx/Tx buffers)
+ 108 PWM Rcvr
+ 152 PPM Rcvr
+ 112 Spektrum Rcvr
+ 24 S.Bus (Should be closer to 68 since driver is still using
static memory)
There are still some drivers that pre-allocate all of their memory
as static data. It'll take some work to convert those over to
dynamically allocating their instance data.
only one CS line is asserted. No checks are enforced on this by the SPI code
as I cant see a clean way of it being aware of the CS lines. We could add
another CS mode those which is driver managed per transfer and has a GPIO i
line for each device.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@2579 ebee16cc-31ac-478f-84a7-5cbb03baadba
PIOS SPI devices may now make use of automatic CRC generation
and checking on block transfers. Only supports CRC8 for now.
Since the SPI interface CRC calculation continues across message
boundaries (ie. not reset on every transfer), we must manually reset
the CRC registers for every transfer to allow the two sides of the
link to resynchronize.
Unfortunately, resetting the CRC registers requires disabling the
SPI peripheral which must now be done on every block transfer.
Note: The last byte of the tx buffer is never sent and is assumed to
be a place holder for the tx CRC8.
Note: The last byte of the rx buffer is expected to hold the rx CRC8.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@1011 ebee16cc-31ac-478f-84a7-5cbb03baadba
Tx buffers should not be modified. This allows passing const data
to the transfer function.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@1010 ebee16cc-31ac-478f-84a7-5cbb03baadba
TransferByte API is simplified to either assert or
return the rx byte.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@999 ebee16cc-31ac-478f-84a7-5cbb03baadba
SPI block transfers were broken in commit r759. Block
transfers are primarily used by the SD card interface so
this also broke accesses to the SD card.
SD card accesses should be fixed now. Verified by writing
config objects in the GCS and confirming that they survived
a reboot of the OP board.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@808 ebee16cc-31ac-478f-84a7-5cbb03baadba
Added support for SPI slave configurations to the pios SPI layer.
Converted the board specific configuration for the PIOS SPI layer to
use const static initializers rather than #defines (see pios_board.c).
SPI interface between the OP board and the AHRS is now operational at
a basic level, capable of moving simple single byte messages between
boards. Multi-byte, CRC protected messages will be added on top of this.
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@759 ebee16cc-31ac-478f-84a7-5cbb03baadba
