]>
Commit | Line | Data |
---|---|---|
1 | ## | |
2 | ## This file is part of the libsigrokdecode project. | |
3 | ## | |
4 | ## Copyright (C) 2016 Daniel Schulte <trilader@schroedingers-bit.net> | |
5 | ## | |
6 | ## This program is free software; you can redistribute it and/or modify | |
7 | ## it under the terms of the GNU General Public License as published by | |
8 | ## the Free Software Foundation; either version 2 of the License, or | |
9 | ## (at your option) any later version. | |
10 | ## | |
11 | ## This program is distributed in the hope that it will be useful, | |
12 | ## but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | ## GNU General Public License for more details. | |
15 | ## | |
16 | ## You should have received a copy of the GNU General Public License | |
17 | ## along with this program; if not, see <http://www.gnu.org/licenses/>. | |
18 | ## | |
19 | ||
20 | import sigrokdecode as srd | |
21 | from collections import namedtuple | |
22 | ||
23 | class Ann: | |
24 | BIT, START, STOP, PARITY_OK, PARITY_ERR, DATA, WORD = range(7) | |
25 | ||
26 | Bit = namedtuple('Bit', 'val ss es') | |
27 | ||
28 | class Decoder(srd.Decoder): | |
29 | api_version = 3 | |
30 | id = 'ps2' | |
31 | name = 'PS/2' | |
32 | longname = 'PS/2' | |
33 | desc = 'PS/2 keyboard/mouse interface.' | |
34 | license = 'gplv2+' | |
35 | inputs = ['logic'] | |
36 | outputs = ['ps2'] | |
37 | tags = ['PC'] | |
38 | channels = ( | |
39 | {'id': 'clk', 'name': 'Clock', 'desc': 'Clock line'}, | |
40 | {'id': 'data', 'name': 'Data', 'desc': 'Data line'}, | |
41 | ) | |
42 | annotations = ( | |
43 | ('bit', 'Bit'), | |
44 | ('start-bit', 'Start bit'), | |
45 | ('stop-bit', 'Stop bit'), | |
46 | ('parity-ok', 'Parity OK bit'), | |
47 | ('parity-err', 'Parity error bit'), | |
48 | ('data-bit', 'Data bit'), | |
49 | ('word', 'Word'), | |
50 | ) | |
51 | annotation_rows = ( | |
52 | ('bits', 'Bits', (0,)), | |
53 | ('fields', 'Fields', (1, 2, 3, 4, 5, 6)), | |
54 | ) | |
55 | ||
56 | def __init__(self): | |
57 | self.reset() | |
58 | ||
59 | def reset(self): | |
60 | self.bits = [] | |
61 | self.samplenum = 0 | |
62 | self.bitcount = 0 | |
63 | ||
64 | def start(self): | |
65 | self.out_ann = self.register(srd.OUTPUT_ANN) | |
66 | ||
67 | def putb(self, bit, ann_idx): | |
68 | b = self.bits[bit] | |
69 | self.put(b.ss, b.es, self.out_ann, [ann_idx, [str(b.val)]]) | |
70 | ||
71 | def putx(self, bit, ann): | |
72 | self.put(self.bits[bit].ss, self.bits[bit].es, self.out_ann, ann) | |
73 | ||
74 | def handle_bits(self, datapin): | |
75 | # Ignore non start condition bits (useful during keyboard init). | |
76 | if self.bitcount == 0 and datapin == 1: | |
77 | return | |
78 | ||
79 | # Store individual bits and their start/end samplenumbers. | |
80 | self.bits.append(Bit(datapin, self.samplenum, self.samplenum)) | |
81 | ||
82 | # Fix up end sample numbers of the bits. | |
83 | if self.bitcount > 0: | |
84 | b = self.bits[self.bitcount - 1] | |
85 | self.bits[self.bitcount - 1] = Bit(b.val, b.ss, self.samplenum) | |
86 | if self.bitcount == 11: | |
87 | self.bitwidth = self.bits[1].es - self.bits[2].es | |
88 | b = self.bits[-1] | |
89 | self.bits[-1] = Bit(b.val, b.ss, b.es + self.bitwidth) | |
90 | ||
91 | # Find all 11 bits. Start + 8 data + odd parity + stop. | |
92 | if self.bitcount < 11: | |
93 | self.bitcount += 1 | |
94 | return | |
95 | ||
96 | # Extract data word. | |
97 | word = 0 | |
98 | for i in range(8): | |
99 | word |= (self.bits[i + 1].val << i) | |
100 | ||
101 | # Calculate parity. | |
102 | parity_ok = (bin(word).count('1') + self.bits[9].val) % 2 == 1 | |
103 | ||
104 | # Emit annotations. | |
105 | for i in range(11): | |
106 | self.putb(i, Ann.BIT) | |
107 | self.putx(0, [Ann.START, ['Start bit', 'Start', 'S']]) | |
108 | self.put(self.bits[1].ss, self.bits[8].es, self.out_ann, [Ann.WORD, | |
109 | ['Data: %02x' % word, 'D: %02x' % word, '%02x' % word]]) | |
110 | if parity_ok: | |
111 | self.putx(9, [Ann.PARITY_OK, ['Parity OK', 'Par OK', 'P']]) | |
112 | else: | |
113 | self.putx(9, [Ann.PARITY_ERR, ['Parity error', 'Par err', 'PE']]) | |
114 | self.putx(10, [Ann.STOP, ['Stop bit', 'Stop', 'St', 'T']]) | |
115 | ||
116 | self.bits, self.bitcount = [], 0 | |
117 | ||
118 | def decode(self): | |
119 | while True: | |
120 | # Sample data bits on falling clock edge. | |
121 | clock_pin, data_pin = self.wait({0: 'f'}) | |
122 | self.handle_bits(data_pin) |