4-channel software trigger output (STRG0~STRG3): Generate a single pulse (pulse width programmable, 60 μ s~16ms) through API for synchronizing strobe lights or external devices.
I/O electrical characteristics: Input high level ≥ 2.0V, low level ≤ 0.8V; output high level ≥ 5.0V (-1.0mA), output low level ≤ 0.5V (100mA current), can directly drive small relays or TTL logic.
All I/O lines are configured on two 10 pin pin banks (CN8, CN9), and can be optionally equipped with RTV-I4 isolated GPIO expansion board, providing photoelectric isolation and relay output (normally open/normally closed optional, contact capacity AC 0.5A/125V or DC 1A/30V), enhancing the anti-interference ability of industrial sites.
3.2 Watchdog Timer
The onboard hardware watchdog (2-pin pin CN10) is an important reliability feature of the RTV-24 series. Enable and set a timeout interval (8 seconds, 16 seconds, or 32 seconds) through the API function AngeloRTV_Set_TDT, and the application needs to periodically "feed the dog" (call this function to reset the timer). If the dog is not fed within the set time, the watchdog will output a system reset signal (which can be connected to the motherboard reset pin through the included reset cable) and automatically restart the PC. This mechanism is crucial for unmanned remote monitoring systems and can effectively prevent equipment shutdown caused by software deadlocks.

Hardware installation and driver deployment
4.1 Key points of physical installation
PCI/PCIe version: Select an available PCI or PCIe x1 slot, insert the card and secure it. If expansion is required, connect the RTV-E4 expansion board to the main card expansion interface using a 10 core flat cable (pay attention to the cable direction and ensure pin 1 is aligned).
CPCI version: cRTV-24 is a 3U board card, inserted into the 32/64 slot of the cPCI backplane, pushed in and locked with the ejector; The cRTV-44 is a 6U card installed in the corresponding slot of the 6U cPCI chassis. CompactPCI supports hot swapping, but requires system platform support.
PMC version: PMC-RTV21 can be directly inserted into the PMC socket of the carrier board, and attention should be paid to anti-static operation.
4.2 Windows Driver Installation (WDM)
Install the driver first, then insert the card (important! To avoid Windows automatically installing the wrong driver).
Insert ADLINK All in One CD, select "Vision" → "Angelo" → "Windows Driver" for installation.
After installation, shut down, insert the RTV series card, and restart.
The system will sequentially discover multiple new devices (one for each video and audio channel, totaling 8 devices), and follow the wizard to automatically install the drivers.
If a yellow exclamation mark appears, you need to manually update the driver and point to the installation directory (such as C: Program Files ADLINK Angelo. RTVDevices Win2KXP).
After installation, you should see 4 "ADLINK Angelo Video Devices" and 4 "Audio Devices" in the "Multimedia Devices" section of the Device Manager.
Vista/7 and above systems: If there is a driver signature issue, press F8 at startup to select "Disable Driver Signature Enforcement" or use test mode.
4.3 Linux Driver Installation (Core Points)
The Linux driver only supports Red Hat 7.3 (kernel 2.4.18), but the principle can be ported to new kernels.
Key steps:
Reserved physical memory: The Bt878 chip uses kernel physical memory as a frame buffer, which needs to be reserved in the boot parameters. For example, if the system has 128MB of RAM and needs to reserve 20MB for 4-channel acquisition, add mem=120MB in the LILO/GRUB kernel parameters (only allowing the kernel to use 120MB, leaving the remaining 8MB for DMA). Each channel requires approximately 5MB, 20MB for 4 channels, and 40MB for 8 channels.
Load kernel module: Extract the driver package tar xvzf angelo2.gz, enter the driver directory, execute insmod - f mem_mgr. o to insert the memory management module, and then execute insmod p878. o to insert the main driver module. Scripts can be used /878. pl<number of channels>automatically completed.
Create device node: The script will automatically create nodes such as/dev/pci878-0.
User state library: Copy libpci_878.so to/usr/lib, and the application can link to the library to call the API.
Common troubleshooting and debugging techniques
No image or black screen:
Use an oscilloscope or monitor to confirm that the BNC signal of the video source is normal (1Vpp, including synchronization head).
Check the return value of AngeloRTV_Detect_Video_fFormat: If it is 0, there is no signal. Check the cable and camera power supply.
Confirm that the video format settings match the actual signal (NTSC/PAL), and try the automatic detection mode.
Image color abnormality or color cast:
Adjust the Hue parameter (NTSC signal specific).
Check if the color format settings match the display or algorithm (e.g. confusion between RGB16 and RGB24 can cause color distortion).
Check if the brightness/contrast/saturation settings are within a reasonable range.