- It turns out that Sony PTZ cameras need DTR/DSR flow control and Canon PTZ cameras need RTS/CTS flow control.
- There must be ports on the serial expansion board with hardware flow control enabled.
- So these ports would require additional INT IN endpoint apart from BULK IN/OUT.
- Also each of these would require 6 FPGA pins from VHDCI.
- So there is an open question - how about having just 2 or 4 of these flow-controlled ports? And rest of them without flow control?
- A majority of serial devices work without flow control, and even these PTZ cameras may work without flow control at very low baud rate. But I don't have PTZ cameras to test so I wouldn't want to take chances.
- And there is another question left for us. Do CDC ACM drivers support Bulk only CDC ACM serial port, i.e. the ones without INT IN endpoint?
- Flow control is also a concern with the Numato board design, because that also seems to ignore RTS/CTS and DTR/DSR flow control. Only RX, TX is used in the schematics that I was shown. While this would work with RS422 pretty well, it might not work with RS232C based cameras.
- There must be ports on the serial expansion board with hardware flow control enabled.
- So these ports would require additional INT IN endpoint apart from BULK IN/OUT.
- Also each of these would require 6 FPGA pins from VHDCI.
- So there is an open question - how about having just 2 or 4 of these flow-controlled ports? And rest of them without flow control?
- A majority of serial devices work without flow control, and even these PTZ cameras may work without flow control at very low baud rate. But I don't have PTZ cameras to test so I wouldn't want to take chances.
- And there is another question left for us. Do CDC ACM drivers support Bulk only CDC ACM serial port, i.e. the ones without INT IN endpoint?
- Flow control is also a concern with the Numato board design, because that also seems to ignore RTS/CTS and DTR/DSR flow control. Only RX, TX is used in the schematics that I was shown. While this would work with RS422 pretty well, it might not work with RS232C based cameras.
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