-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I've been very slowly reading (and trying to run thru gdb) the item parsing and fetching/scaling code in libusbhid. I have to admit I have not yet fully figured out what's happening, but what I have seen, so far, are a couple of different comments that the spec isn't clear about the type (signed or unsigned) of the data.
reading from /usr/src/lib/libusbhid/parse.c:209, "The spec is unclear if the data is signed or unsigned." That's only one of the comments I found, all saying about the same thing. Least I remember 2 of them. Well, let me first admit, right away, this is the spec from hell, and anyone saying this is a good spec (and I have seen such on the web) are just declaring themselves as not having enough experience reading specs. This IS the spec from hell. Nevertheless, it IS pretty clear about the type of data. I refer you to page 38 of the spec, top paragraph on the page: _HID spec excerpt, page 38 top: "Main items are used to either define or group certain types of data fields within a Report descriptor. There are two types of Main items: data and non-data. Data-type Main items are used to create a field within a report and include Input, Output, and Feature. Other items do not create fields and are subsequently referred to as non-data Main items." (end spec excerpt) At least for my data, all the data is definitely unsigned, and it's very important that this be followed. I don't think libusbhid is doing this (although I haven't yet been able to get hid_get_data() to return anything except 0 so far). However, realize (like I said) this is a horrible spec, and one could not blame anyone at all for misreading it. Even me. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4 (FreeBSD) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFITAzNz62J6PPcoOkRAljKAJ9dWxTRN1EgKaTR4bEe48cG01UkiQCZAVCv j8bYvjYWGuvQ92TCMH5XM0o= =g59X -----END PGP SIGNATURE----- _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-usb To unsubscribe, send any mail to "[EMAIL PROTECTED]"
