This is an old revision of the document!
Controlling the camera is done via writing “registers” - think of them as address locations. There are generally 4 ways to interface with the camera from a host:
- standard UVC - this one is automagically supported by any UVC 1.1 compliant OS, which in the year 2017 would be “any modern OS”. This interface covers the universally standardized controls for USB Video Class
- (Gen 3 and Gen 4) direct I²C access via Cypress's FX3 interface, using control port
0x20
. This allows access to all sensor's registers (at your own risk!). For more information search the web for documentation on the sensor in your camera (as of October 2017 that would be OmniVision 10823 sensor) - FX3 Host Vendor Command Interface - this interfaces with the Cypress's FX3 and is the primary FX3 API
- FPGA I²C Access - a “window” into a host of additional commands that are performed on FPGA, this is highly dependent on the FPGA model used and camera's generation and is not exactly intended for direct use outside of developing FX3 APIs and during development cycle of GUI implementation. The FPGA register maps are defined on this page
The last two (FX3 HVCI and FPGA I²C) are described in FX3 HVCI and FPGA I²C commands.
If you are set on writing your own UI and don't want to be bothered too much with figuring out how to communicate with the camera you have an option of using the SUB2r-lib library (which should be your preference anyways).
More details
SUB2r camera is built on a Cypress FX3 chipset that facilitates the Super-Speed USB 3.0+
communication between the device and a host system. Every component of the camera, be it an FPGA or an image sensor, receives user commands via that Cypress FX3.
On Windows the device is registered with a GUID {36FC9E60-C465-11CF-8056-444553540000}
and if you are not planning on using the SUB2r-lib
for your development - that would be the GUID to search for to properly connect to the command channel.
Here's a sample code that shows how to send commands to both the FX3 Host (defined on this page) and to access FPGA's mapped registers
. The code lacks error checking (for clarity) and this should go without saying that if you copy-paste it into your code you must add error handling :)
// set a new auto-functions' update interval to 2x the default // just issue the command directly to FX3's vendor request interface void setAUInterval(){ S2R::FX3 fx3; fx3.open(0); fx3.vrCmd(S2R::FX3::af_au_period, S2R::FX3::write, 6000, 0); } // run DPC calibration - also just a straight-up vendor request command to FX3 void runDPC(UCHAR _threshold = 240){ S2R::FX3 fx3; fx3.open(0); fx3.vrCmd(S2R::FX3::calibrate_dpc, S2R::FX3::write, _threshold, 0); } // increase LED's green brightness by 25% // utilize the FPGA's I²C bridge void lightUpTheGreen(){ using Cmd = S2R::FX3::Fx3Cmd; using OpType = S2R::FX3::VrCmdOpType; S2R::FX3 fx3; fx3.open(0); uint8_t buf[1]{0}; // LED green is mapped to register 0x0A ONLY for Gen3 and Gen4, won't work for Gen5 const uint16_t clrChannel{0x0A}; fx3.vrCmd(Cmd::i2c_bridge_fpga, OpType::read, 0, clrChannel, buf, 1); buf[0] += buf[0] / 4; // yes, this can totally overflow fx3.vrCmd(Cmd::i2c_bridge_fpga, OpType::write, buf[0], clrChannel); }
Firmware Version Info
This applies to both FX3 and FPGA firmware version info data structures.
Bit layout
The bits are laid out in 4 sequential bytes as follows:
3 | 2 | 1 | 0 | ||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
buildNo[12:5] | buildNo[4:0] | releaseType | productId | hwCfgId | vendorId |
Firmware version info C/C++-struct
The FX3 version structure is as follows (little-endian memory layout):
- firmware-version.h
struct FwVersion{ unsigned vendorId : 3; unsigned hwCfgId : 5; unsigned productId : 8; unsigned releaseType : 3; unsigned buildNo : 13; }; static_assert(sizeof(FwVersion) == 4);
FX3 Version Info
The version id is also encoded into the firmware image file name as:
<VendorID>_<HardwareID>_<ProductID>_<ReleaseType>_<BuildNumber>
Code | Value |
Vendor ID | |
---|---|
1 | Cypress |
Hardware ID | |
1 | FX3 Gen1 |
Product ID | |
1 | reserved for Gen 1 camera, a.k.a. “Moon landing” |
2 | reserved for Gen 2 camera, a.k.a. “Piggy” |
3 | Gen 3 camera (Alpha), a.k.a. “Frankie” (from Frankenstein's Monster) |
4 | Gen 3 camera, Production |
5 | Gen 4 camera, a.k.a. “Vitreledonella” |
6 | Gen 5 camera, either “Square One” or “Studio” |
Release type | |
0 | Private build: Private build for debugging and similar purposes |
1 | Alpha: feature-incomplete early development cycle “somewhat stable” build |
2 | Beta: feature-complete, but not very stable build (lots of bugs) |
3 | Evaluation: Tech preview |
4 | Release candidate: feature complete and stable |
5 | Release: general availability |
6 | Backport: backport of a feature from next gen camera |
7 | Emergency bug fix: a critical post-release bugfix |
Build number | |
# | Increments on each build |
FPGA Version Info
The version id is also encoded into the firmware image file name as:
<VendorID>_<HardwareID>_<ProductID>_<ReleaseType>_<BuildNumber>
Vendor ID that represents a vendor of the main computation unit | |
---|---|
Code | Value |
1 | Xilinx (AMD) |
2 | Altera (Intel) |
Hardware ID for VendorId 1 (Xylinx) | |
---|---|
Code | Value |
1 | Artix-7 100T |
2 | Artix-7 200T |
3 | Artix UltraScale+ XCAU25P |
Hardware ID for VendorId 2 (Altera) | |
---|---|
Code | Value |
1 | Cyclone 10 GX |
Product ID | |
---|---|
Code | Value |
1 | reserved |
2 | reserved |
3 | Gen 3 camera (Alpha), a.k.a. “Frankie” |
4 | Gen 3 camera, Production |
5 | Gen 4 camera, a.k.a. “Vitreledonella” |
6 | Gen 5 camera, prosumer grade “Square One” |
7 | Gen 5 camera, professional grade “Studio” |
Release type | |
---|---|
Code | Value |
0 | Private build |
1 | Alpha |
2 | Beta |
3 | Eval/Tech preview |
4 | Release candidate |
5 | Release |
6 | Backport |
7 | Emergency bug fix |
Build number | |
---|---|
Code | Value |
# | 11 bits of a build number (the range is 1..2047 ). Increments on each build |