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.
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.
It's not an Si5351C driver thing, but a HackRF thing. Also added a driver function to check if CLKIN signal is valid, and made use of it, instead of opaque register read code.
=======================================
This commit allows to synchronise multiple HackRFs with a synchronisation error **below 1 sampling period**
> WARNING: Use this at your own risk. If you don't know what you are doing you may damage your HackRF.
> The author takes no responsability for potential damages
Usage example: synchronise two HackRFs
======================================
1. Chose the master HackRF which will send the synchronisation pulse (HackRF0). HackRF1 will represent the slave hackrf.
2. Retreive the serial number of both HackRFs using `hackrf_info`
3. Use a wire to connect `SYNC_CMD` of HackRF0 to `SYNC_IN` of HackRF0 and HackRF1
4. Run `hackrf_transfer` with the argument `-H 1` to enable hardware synchronisation:
```
$ hackrf_tranfer ... -r rec1.bin -d HackRF1_serial -H 1 | hackrf_transfer ... -r rec0.bin -d HackRF0_serial -H 1
```
rec0.bin and rec1.bin will have a time offset below 1 sampling period.
The 1PPS output of GNSS receivers can be used to synchronise HackRFs even if they are far from each other.
>DON'T APPLY INCOMPATIBLE VOLTAGE LEVELS TO THE CPLD PINS
Signal | Header |Pin | Description
-------|--------|----|------------
`SYNC_IN` | P28 | 16 | Synchronisation pulse input
`SYNC_CMD` | P28 | 15 | Synchronisation pulse output
Note:
=====
I had to remove CPLD-based decimation to use a GPIO for enabling hardware.
More info:
==========
[M. Bartolucci, J. A. Del Peral-Rosado, R. Estatuet-Castillo, J. A. Garcia-Molina, M. Crisci and G. E. Corazza, "Synchronisation of low-cost open source SDRs for navigation applications," 2016 8th ESA Workshop on Satellite Navigation Technologies and European Workshop on GNSS Signals and Signal Processing (NAVITEC), Noordwijk, 2016, pp. 1-7.](http://ieeexplore.ieee.org/document/7849328/)
[Alternative link](http://spcomnav.uab.es/docs/conferences/Bartolucci_NAVITEC_2016.pdf)
Just a very rough merge to get off the ground. Major parts are not yet
implemented. The mixer intergration is in a messed up state. Part which
need work have been marked with XXX
Conflicts:
firmware/common/hackrf_core.c
firmware/common/hackrf_core.h
firmware/common/max2837.c
firmware/common/max2837.h
firmware/common/rf_path.c
firmware/common/rffc5071.c
firmware/common/rffc5071.h
firmware/common/sgpio.c
firmware/common/si5351c.c
firmware/common/tuning.c
firmware/common/w25q80bv.c
firmware/common/w25q80bv.h
firmware/common/xapp058/ports.c
firmware/hackrf-common.cmake
firmware/hackrf_usb/hackrf_usb.c
firmware/hackrf_usb/usb_api_register.c
firmware/hackrf_usb/usb_api_transceiver.c
host/hackrf-tools/src/hackrf_transfer.c
