blob: 555dc7f90578d16b3cf7fd1e46ab5369c381b8ac (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
|
##
## This file is part of the libsigrokdecode project.
##
## Copyright (C) 2012 Uwe Hermann <uwe@hermann-uwe.de>
##
## This program is free software; you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published by
## the Free Software Foundation; either version 2 of the License, or
## (at your option) any later version.
##
## This program is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
## GNU General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with this program; if not, write to the Free Software
## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
##
'''
USB (low-speed and full-speed) packet protocol decoder.
Protocol layer (USB spec, chapter 8):
Bit/byte ordering: Bits are sent onto the bus LSB-first. Multibyte fields
are transmitted in little-endian order (i.e., LSB to MSB).
SYNC field: All packets begin with a SYNC field (8 bits).
Packet field format: Packets start with an SOP (Start Of Packet) delimiter
that is part of the SYNC field, and end with an EOP (End Of Packet).
PID: A PID (packet identifier) follows the SYNC field of every packet. A PID
consists of a 4-bit packet type field, and a 4 bit check field.
The check field is the one's complement of the packet type field.
Protocol output format:
TODO
Details:
https://en.wikipedia.org/wiki/USB
http://www.usb.org/developers/docs/
'''
from .pd import *
|
