+++ /dev/null
-##
-## This file is part of the sigrok 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
-##
-
-# National LM75 (and compatibles) temperature sensor protocol decoder
-
-# TODO: Better support for various LM75 compatible devices.
-
-import sigrokdecode as srd
-
-# LM75 only supports 9 bit resolution, compatible devices usually 9-12 bits.
-resolution = {
- # CONFIG[6:5]: <resolution>
- 0x00: 9,
- 0x01: 10,
- 0x02: 11,
- 0x03: 12,
-}
-
-ft = {
- # CONFIG[4:3]: <fault tolerance setting>
- 0x00: 1,
- 0x01: 2,
- 0x02: 4,
- 0x03: 6,
-}
-
-class Decoder(srd.Decoder):
- api_version = 1
- id = 'lm75'
- name = 'LM75'
- longname = 'National LM75'
- desc = 'National LM75 (and compatibles) temperature sensor protocol.'
- license = 'gplv2+'
- inputs = ['i2c']
- outputs = ['lm75']
- probes = []
- optional_probes = [
- {'id': 'os', 'name': 'OS', 'desc': 'Overtemperature shutdown'},
- {'id': 'a0', 'name': 'A0', 'desc': 'I2C slave address input 0'},
- {'id': 'a1', 'name': 'A1', 'desc': 'I2C slave address input 1'},
- {'id': 'a2', 'name': 'A2', 'desc': 'I2C slave address input 2'},
- ]
- options = {
- 'sensor': ['Sensor type', 'lm75'],
- 'resolution': ['Resolution', 9], # 9-12 bit, sensor/config dependent
- }
- annotations = [
- ['Celsius', 'Temperature in degrees Celsius'],
- ['Kelvin', 'Temperature in Kelvin'],
- ['Text (verbose)', 'Human-readable text (verbose)'],
- ['Text', 'Human-readable text'],
- ['Warnings', 'Human-readable warnings'],
- ]
-
- def __init__(self, **kwargs):
- self.state = 'IDLE'
- self.reg = 0x00 # Currently selected register
- self.databytes = []
- self.mintemp = 0
- self.maxtemp = 0
- self.avgvalues = []
-
- def start(self, metadata):
- # self.out_proto = self.add(srd.OUTPUT_PROTO, 'lm75')
- self.out_ann = self.add(srd.OUTPUT_ANN, 'lm75')
-
- def report(self):
- # TODO: print() or self.put() or return xyz, or... ?
- avg = sum(self.avgvalues) / len(self.avgvalues)
- temperatures = (self.mintemp, self.maxtemp, avg)
- # TODO: Configurable report() output, e.g. for Kelvin.
- return 'Min/max/avg temperature: %f/%f/%f °C' % temperatures
-
- def putx(self, data):
- # Helper for annotations which span exactly one I2C packet.
- self.put(self.ss, self.es, self.out_ann, data)
-
- def putb(self, data):
- # Helper for annotations which span a block of I2C packets.
- self.put(self.block_start, self.block_end, self.out_ann, data)
-
- def warn_upon_invalid_slave(self, addr):
- # LM75 and compatible devices have a 7-bit I2C slave address where
- # the 4 MSBs are fixed to 1001, and the 3 LSBs are configurable.
- # Thus, valid slave addresses (1001xxx) range from 0x48 to 0x4f.
- if addr not in range(0x48, 0x4f + 1):
- s = 'Warning: I2C slave 0x%02x not an LM75 compatible sensor.'
- self.putx([4, [s % addr]])
-
- def output_temperature(self, s, rw):
- # TODO: Support for resolutions other than 9 bit.
- before, after = self.databytes[0], (self.databytes[1] >> 7) * 5
- celsius = float('%d.%d' % (before, after))
- kelvin = celsius + 273.15
- self.putb([0, ['%s: %.1f °C' % (s, celsius)]])
- self.putb([1, ['%s: %.1f K' % (s, kelvin)]])
-
- # Warn about the temperature register (0x00) being read-only.
- if s == 'Temperature' and rw == 'WRITE':
- s = 'Warning: The temperature register is read-only!'
- self.putb([4, [s]])
-
- # Keep some statistics. Can be output in report(), for example.
- if celsius < self.mintemp:
- self.mintemp = celsius
- if celsius > self.maxtemp:
- self.maxtemp = celsius
- self.avgvalues.append(celsius)
-
- def handle_temperature_reg(self, b, s, rw):
- # Common helper for the temperature/T_HYST/T_OS registers.
- if len(self.databytes) == 0:
- self.block_start = self.ss
- self.databytes.append(b)
- return
- self.databytes.append(b)
- self.block_end = self.es
- self.output_temperature(s, rw)
- self.databytes = []
-
- def handle_reg_0x00(self, b, rw):
- # Temperature register (16bits, read-only).
- self.handle_temperature_reg(b, 'Temperature', rw)
-
- def handle_reg_0x01(self, b, rw):
- # Configuration register (8 bits, read/write).
- # TODO: Bit-exact annotation ranges.
-
- sd = b & (1 << 0)
- tmp = 'normal operation' if (sd == 0) else 'shutdown mode'
- s = 'SD = %d: %s\n' % (sd, tmp)
- s2 = 'SD = %s, ' % tmp
-
- cmp_int = b & (1 << 1)
- tmp = 'comparator' if (cmp_int == 0) else 'interrupt'
- s += 'CMP/INT = %d: %s mode\n' % (cmp_int, tmp)
- s2 += 'CMP/INT = %s, ' % tmp
-
- pol = b & (1 << 2)
- tmp = 'low' if (pol == 0) else 'high'
- s += 'POL = %d: OS polarity is active-%s\n' % (pol, tmp)
- s2 += 'POL = active-%s, ' % tmp
-
- bits = (b & ((1 << 4) | (1 << 3))) >> 3
- s += 'Fault tolerance setting: %d bit(s)\n' % ft[bits]
- s2 += 'FT = %d' % ft[bits]
-
- # Not supported by LM75, but by various compatible devices.
- if self.options['sensor'] != 'lm75': # TODO
- bits = (b & ((1 << 6) | (1 << 5))) >> 5
- s += 'Resolution: %d bits\n' % resolution[bits]
- s2 += ', resolution = %d' % resolution[bits]
-
- self.putx([2, [s]])
- self.putx([3, [s2]])
-
- def handle_reg_0x02(self, b, rw):
- # T_HYST register (16 bits, read/write).
- self.handle_temperature_reg(b, 'T_HYST trip temperature', rw)
-
- def handle_reg_0x03(self, b, rw):
- # T_OS register (16 bits, read/write).
- self.handle_temperature_reg(b, 'T_OS trip temperature', rw)
-
- def decode(self, ss, es, data):
- cmd, databyte = data
-
- # Store the start/end samples of this I2C packet.
- self.ss, self.es = ss, 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 read/write operation.
- if cmd in ('ADDRESS READ', 'ADDRESS WRITE'):
- self.warn_upon_invalid_slave(databyte)
- self.state = cmd[8:] + ' REGS' # READ REGS / WRITE REGS
- elif self.state in ('READ REGS', 'WRITE REGS'):
- if cmd in ('DATA READ', 'DATA WRITE'):
- handle_reg = getattr(self, 'handle_reg_0x%02x' % self.reg)
- handle_reg(databyte, cmd[5:]) # READ / WRITE
- elif cmd == 'STOP':
- # TODO: Any output?
- self.state = 'IDLE'
- else:
- # self.putx([0, ['Ignoring: %s (data=%s)' % (cmd, databyte)]])
- pass
- else:
- raise Exception('Invalid state: %s' % self.state)
-
projects / libsigrokdecode.git / blobdiff