--- /dev/null
+##
+## This file is part of the libsigrokdecode project.
+##
+## Copyright (C) 2020 Analog Devices Inc.
+##
+## 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 3 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, see <http://www.gnu.org/licenses/>.
+##
+
+import sigrokdecode as srd
+
+slave_address = {
+ 0x00: ['GND', 'GND', 'GND', 'G'],
+ 0x01: ['FLOAT', 'FLOAT', 'FLOAT', 'F'],
+ 0x02: ['VCC', 'VCC', 'VCC', 'V'],
+}
+
+commands = {
+ 0x00: ['Write Input Register', 'Write In Reg', 'Wr In Reg', 'WIR'],
+ 0x01: ['Update DAC', 'Update', 'U'],
+ 0x03: ['Write and Power Up DAC', 'Write & Power Up', 'W&PU'],
+ 0x04: ['Power Down DAC', 'Power Down', 'PD'],
+ 0x0F: ['No Operation', 'No Op', 'NO'],
+}
+
+addresses = {
+ 0x00: ['DAC A', 'A'],
+ 0x01: ['DAC B', 'B'],
+ 0x0F: ['All DACs', 'All'],
+}
+
+input_voltage_format = ['%fV', '%fV', '%.6fV', '%.2fV']
+
+class Decoder(srd.Decoder):
+ api_version = 3
+ id = 'ltc26x7'
+ name = 'LTC26x7'
+ longname = 'Linear Technology LTC26x7'
+ desc = 'Linear Technology LTC26x7 16-/14-/12-bit rail-to-rail DACs.'
+ license = 'gplv2+'
+ inputs = ['i2c']
+ outputs = []
+ tags = ['Display']
+ options = (
+ {'id': 'part', 'desc': 'Part', 'default': 'ltc26x7',
+ 'values': ('ltc2607', 'ltc2617', 'ltc2627')},
+ {'id': 'ref', 'desc': 'Reference voltage', 'default': 1.5},
+ )
+ annotations = (
+ ('slave_addr', 'Slave address'),
+ ('command', 'Command'),
+ ('address', 'Address'),
+ ('data', '2 byte data'),
+ )
+ annotation_rows = (
+ ('ltc26x7', 'LTC26x7 data', (0, 1, 2, 3)),
+ )
+
+ def __init__(self):
+ self.reset()
+
+ def reset(self):
+ self.state = 'IDLE'
+ self.ss = -1
+ self.data = 0x00
+
+ def start(self):
+ self.out_ann = self.register(srd.OUTPUT_ANN)
+
+ def convert_ternary_str(self, n):
+ if n == 0:
+ return [0, 0, 0]
+ nums = []
+ while n:
+ n, r = divmod(n, 3)
+ nums.append(r)
+ while len(nums) < 3:
+ nums.append(0)
+ return list(reversed(nums))
+
+ def handle_slave_addr(self, data):
+ if data == 0x73:
+ ann = ['Global address', 'Global addr', 'Glob addr', 'GA']
+ self.put(self.ss, self.es, self.out_ann, [0, ann])
+ return
+ ann = ['CA2=%s CA1=%s CA0=%s', '2=%s 1=%s 0=%s', '%s %s %s', '%s %s %s']
+ addr = 0
+ for i in range(7):
+ if i in [2, 3]:
+ continue
+ offset = i
+ if i > 3:
+ offset -= 2
+ mask = 1 << i
+ if data & mask:
+ mask = 1 << offset
+ addr |= mask
+
+ addr -= 0x04
+ ternary_values = self.convert_ternary_str(addr)
+ for i in range(len(ann)):
+ ann[i] = ann[i] % (slave_address[ternary_values[0]][i],
+ slave_address[ternary_values[1]][i],
+ slave_address[ternary_values[2]][i])
+ self.put(self.ss, self.es, self.out_ann, [0, ann])
+
+ def handle_cmd_addr(self, data):
+ cmd_val = (data >> 4) & 0x0F
+ dac_val = (data & 0x0F)
+ sm = (self.ss + self.es) // 2
+
+ self.put(self.ss, sm, self.out_ann, [1, commands[cmd_val]])
+ self.put(sm, self.es, self.out_ann, [2, addresses[dac_val]])
+
+ def handle_data(self, data):
+ self.data = (self.data << 8) & 0xFF00
+ self.data += data
+ if self.options['part'] == 'ltc2617':
+ self.data = (self.data >> 2)
+ self.data = (self.options['ref'] * self.data) / 0x3FFF
+ elif self.options['part'] == 'ltc2627':
+ self.data = (self.data >> 4)
+ self.data = (self.options['ref'] * self.data) / 0x0FFF
+ else:
+ self.data = (self.options['ref'] * self.data) / 0xFFFF
+ ann = []
+ for format in input_voltage_format:
+ ann.append(format % self.data)
+ self.data = 0
+
+ self.put(self.ss, self.es, self.out_ann, [3, ann])
+
+ def decode(self, ss, es, data):
+ cmd, databyte = data
+ self.es = es
+
+ # State machine.
+ if self.state == 'IDLE':
+ # Wait for an I²C START condition.
+ if cmd != 'START':
+ return
+ self.state = 'GET SLAVE ADDR'
+ elif self.state == 'GET SLAVE ADDR':
+ # Wait for an address write operation.
+ if cmd != 'ADDRESS WRITE':
+ return
+ self.ss = ss
+ self.handle_slave_addr(databyte)
+ self.ss = -1
+ self.state = 'GET CMD ADDR'
+ elif self.state == 'GET CMD ADDR':
+ if cmd != 'DATA WRITE':
+ return
+ self.ss = ss
+ self.handle_cmd_addr(databyte)
+ self.ss = -1
+ self.state = 'WRITE DATA'
+ elif self.state == 'WRITE DATA':
+ if cmd == 'DATA WRITE':
+ if self.ss == -1:
+ self.ss = ss
+ self.data = databyte
+ return
+ self.handle_data(databyte)
+ self.ss = -1
+ elif cmd == 'STOP':
+ self.state = 'IDLE'
+ else:
+ return
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