2 ## This file is part of the libsigrokdecode project.
4 ## Copyright (C) 2012 Uwe Hermann <uwe@hermann-uwe.de>
5 ## Copyright (C) 2013 Matt Ranostay <mranostay@gmail.com>
6 ## Copyright (C) 2014 alberink <alberink@stampfini.org>
8 ## This program is free software; you can redistribute it and/or modify
9 ## it under the terms of the GNU General Public License as published by
10 ## the Free Software Foundation; either version 2 of the License, or
11 ## (at your option) any later version.
13 ## This program is distributed in the hope that it will be useful,
14 ## but WITHOUT ANY WARRANTY; without even the implied warranty of
15 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 ## GNU General Public License for more details.
18 ## You should have received a copy of the GNU General Public License
19 ## along with this program; if not, see <http://www.gnu.org/licenses/>.
22 import sigrokdecode as srd
24 class Decoder(srd.Decoder):
28 longname = 'Texas Instruments TCA6408A'
29 desc = 'Texas Instruments TCA6408A 8-bit I²C I/O expander.'
32 outputs = ['tca6408a']
34 ('register', 'Register type'),
35 ('value', 'Register value'),
36 ('warnings', 'Warning messages'),
39 ('regs', 'Registers', (0, 1)),
40 ('warnings', 'Warnings', (2,)),
48 self.out_ann = self.register(srd.OUTPUT_ANN)
51 self.put(self.ss, self.es, self.out_ann, data)
53 def handle_reg_0x00(self, b):
54 self.putx([1, ['State of inputs: %02X' % b]])
56 def handle_reg_0x01(self, b):
57 self.putx([1, ['Outputs set: %02X' % b ]])
59 def handle_reg_0x02(self, b):
60 self.putx([1, ['Polarity inverted: %02X' % b]])
62 def handle_reg_0x03(self, b):
63 self.putx([1, ['Configuration: %02X' % b]])
65 def handle_write_reg(self, b):
67 self.putx([0, ['Input port', 'In', 'I']])
69 self.putx([0, ['Output port', 'Out', 'O']])
71 self.putx([0, ['Polarity inversion register', 'Pol', 'P']])
73 self.putx([0, ['Configuration register', 'Conf', 'C']])
75 def check_correct_chip(self, addr):
76 if addr not in (0x20, 0x21):
77 self.putx([2, ['Warning: I²C slave 0x%02X not a TCA6408A '
78 'compatible chip.' % addr]])
81 def decode(self, ss, es, data):
84 # Store the start/end samples of this I²C packet.
85 self.ss, self.es = ss, es
88 if self.state == 'IDLE':
89 # Wait for an I²C START condition.
92 self.state = 'GET SLAVE ADDR'
93 elif self.state == 'GET SLAVE ADDR':
95 self.state = 'GET REG ADDR'
96 elif self.state == 'GET REG ADDR':
97 # Wait for a data write (master selects the slave register).
98 if cmd in ('ADDRESS READ', 'ADDRESS WRITE'):
99 self.check_correct_chip(databyte)
100 if cmd != 'DATA WRITE':
103 self.handle_write_reg(self.reg)
104 self.state = 'WRITE IO REGS'
105 elif self.state == 'WRITE IO REGS':
106 # If we see a Repeated Start here, the master wants to read.
107 if cmd == 'START REPEAT':
108 self.state = 'READ IO REGS'
110 # Otherwise: Get data bytes until a STOP condition occurs.
111 if cmd == 'DATA WRITE':
112 handle_reg = getattr(self, 'handle_reg_0x%02x' % self.reg)
117 elif self.state == 'READ IO REGS':
118 # Wait for an address read operation.
119 if cmd == 'ADDRESS READ':
120 self.state = 'READ IO REGS2'
123 elif self.state == 'READ IO REGS2':
124 if cmd == 'DATA READ':
125 handle_reg = getattr(self, 'handle_reg_0x%02x' % self.reg)