Reliable oscillator start-up requires several hundred milliseconds which
is longer than we are willing to wait at every boot. We could add an
on-demand test in the future instead of an automatic self-test.
Counter-intuitively, this actually saves us two cycles because we unroll
the first iteration of the loop that spins on the interrupt flag, saving
a branch in the case that the flag is clear the first time.
* Initial commit of hackrf_biast
* Cleaned up hackrf_biast
* Cleaned up usage info
* Include getopt.h for non-GNU systems
* Add support for overriding HackRF's default antenna power behavior in firmware. Add support for specifying antenna power behavior in libhackrf.
* Moved bias tee config routines into user_config.c, cleaned up operation of hackrf_biast
* hackrf_biast now calls usage() and exits when invoked with no arguments
* Fixed minor documentation error in usage()
* minor syntax cleanup
* Add some documentation to the host API call
* Add proper declaration magic in hackrf.h to hackrf_set_user_bias_t_opts() to appease Visual Studio
* Documentation changes suggested by @martinling
* Moved bias t setting above switch statement, removed line that explicit turned bias t off when entering OFF mode
* Change hackrf_set_user_bias_t_opts() to use a friendly struct() instead of a bitmask. User friendliness fixes to hackrf_biast options. More clang-format appeasement.
* Removed support for integer mode args from hackrf_biast
* clang-format error fixes
* Tweaked position of comment for clang-format v14
* Reformat files with clang-format v14 instead of 16
* Remove internal numeric modes for bias T settings
Co-authored-by: Martin Ling <martin-github@earth.li>
* Fix documentation error in hackrf_biast.c
---------
Co-authored-by: Martin Ling <martin-github@earth.li>
During r9 hardware development it was thought that the MAX2839 would use
a different GPIO pin for chip select, but it ended up being the same pin
as is used for MAX2837 on other hardware revisions.
This takes the MAX283x abstraction a bit further and fixes a bug with
hackrf_debug -m.
The bootloader is configured by pin straps on certain pins. We use some
of those for other purposes in r9 which causes the bootloader to
misbehave if the device is reset from software. By switching these pins
from outputs to inputs just before reset this problem is avoided.
The rad1o was not starting the M0 when powered up by inserting a USB
cable. Interestingly the M0 does start when toggling the power switch.
Resetting the M0 before starting it in `main()` solves this issue.
Firmware now detects the hardware it is running on at startup and
refuses to run if it is compiled for the wrong platform. The board ID
returned by firmware to the host is now derived from run-time detection
rather than a compile-time value. A separate method to retrieve
compile-time supported platform is added.
On HackRF One, pin straps are checked to determine hardware revision.
This is informational to aid troubleshooting and does not affect any
function.
On rad1o, the UI update could block this loop from running for long
enough that it could stall in a state where neither of the conditions
was met.
Fix this by removing the 'phase' variable, in favour of a counter
tracking the number of bytes that have been scheduled for USB transfer.
Whenever there are enough bytes to schedule the next transfer, do so.
Meanwhile, the M0 count is prevented from wrapping around and clobbering
data not yet sent, because the M0 code monitors the m4_count variable
which is updated as each transfer completes.
This change avoids various possible races in which an autonomous mode
change by the M0 might clobber a mode change made from the M4, as well
as related races on other state fields that can be written by the M4.
The previous mode field is replaced by two separate ones:
- active_mode, which is written only by the M0, and indicates the
current operating mode.
- requested_mode, which is written by the M4 to request a change.
This field includes both the requested mode, and a flag bit. The M4
writes the field with the flag bit set, and must then wait for the
M0 to signal completion of the request by clearing the flag bit.
Whilst the M4 is blocked waiting for the flag bit to be cleared, the
M0 can safely make all the required changes to the state that are
needed for the transition to the requested mode. Once the transition
is complete, the M0 clears the flag bit and the M4 continues execution.
Request handling is implemented in the idle loop. To handle requests,
mode-specific loops simply need to check the request flag and branch to
idle if it is set.
A request from the M4 to change modes will always require passing
through the idle loop, and is not subject to timing guarantees. Only
transitions made autonomously by the M0 have guaranteed timing
constraints.
The work previously done in reset_counts is now implemented as part of
the request handling, so the tx_start, rx_start and wait_start labels
are no longer required.
An extra two cycles are required in the TX shortfall path because we
must now load the active mode to check whether we are in TX_START.
Two cycles are saved in the normal TX path because updating the active
mode to TX_RUN can now be done without checking the previous value.
Previously, finding the M0 in IDLE mode was ambiguous; it could indicate
either a normal outcome, or a shortfall limit having being hit.
To disambiguate, we add an error field to the M0 state. The errors
currently possible are an RX timeout or a TX timeout, both of which
can be obtained efficiently from the current operating mode due to
the values used.
This adds 3 cycles to both shortfall paths, in order to shift down
the mode to obtain the error code, and store it to the M0 state.
