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Connection to Keyboard

3.15. Connection to Keyboard

The Linux/IrDA keyboard driver is now in user-space. Please see chapter Connection to Docking Station above.

Lichen Wang: "The so called IrDA-D standard is designed to transfer Data. It is not suitable for IR Keyboard. IrDA-D is what Dag ported to Linux OS and what MS ported to Windows OS.

The so called IrDA-C (Control) is designed for Keyboard, Joy-stick, etc. I am not aware that there is any product in the market that is using it yet.

IrDA-D cannot talk to IrDA-C. IrDA-C cannot talk to IrDA-D either. Both the physical encoding/decoding and the software protocol are very different.

It is possible to implement both IrDA-D and IrDA-C in the same device. Sharp says that IrDA-D and IrDA-C can coexist -- as long as both of them are not used at the same time in the same IR space. This sounds rather funny to me. According to this definition, anything can co-exist with anything as long as you do not destroy the universe permanently in the process ;-)

Seriously, what SHARP says is that they can tailor the IrDA-D so that there are some unused time between the negotiated maximum turnaround time and the actual transmission. They then squeeze the IrDA-C frames in those unused time. The IrDA-D Primary and IrDA-C Master must be implemented in the same device. The keyboards will work, but mice and joysticks may be sluggish at times."