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Diffstat (limited to 'decoders/mxc6225xu/mxc6225xu.py')
| -rw-r--r-- | decoders/mxc6225xu/mxc6225xu.py | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/decoders/mxc6225xu/mxc6225xu.py b/decoders/mxc6225xu/mxc6225xu.py new file mode 100644 index 0000000..d3113b2 --- /dev/null +++ b/decoders/mxc6225xu/mxc6225xu.py @@ -0,0 +1,193 @@ +## +## 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 +## + +# MEMSIC MXC6225XU protocol decoder + +import sigrokdecode as srd + +# ... +status = { + # SH[1:0] + 'sh': { + 0b00: 'no shake event', + 0b01: 'shake left', + 0b10: 'shake right', + 0b11: 'undefined', + }, + # ORI[1:0] and OR[1:0] (same format) + 'ori': { + 0b00: 'vertical in upright orientation', + 0b01: 'rotated 90 degrees clockwise', + 0b10: 'vertical in inverted orientation', + 0b11: 'rotated 90 degrees counterclockwise', + }, +} + +class Decoder(srd.Decoder): + api_version = 1 + id = 'mxc6225xu' + name = 'MXC6225XU' + longname = 'MEMSIC MXC6225XU' + desc = 'Digital Thermal Orientation Sensor (DTOS) protocol' + license = 'gplv2+' + inputs = ['i2c'] + outputs = ['mxc6225xu'] + probes = [] + optional_probes = [ + {'id': 'int', 'name': 'INT', 'desc': 'DTOS interrupt output pin'}, + ] + options = {} + annotations = [ + ['TODO', 'TODO'], + ] + + def __init__(self, **kwargs): + self.state = 'IDLE' + + def start(self, metadata): + # self.out_proto = self.add(srd.OUTPUT_PROTO, 'mxc6225xu') + self.out_ann = self.add(srd.OUTPUT_ANN, 'mxc6225xu') + + def report(self): + pass + + def putx(self, data): + self.put(self.ss, self.es, self.out_ann, data) + + def handle_reg_0x00(self, b): + # XOUT: 8-bit x-axis acceleration output. + # Data is in 2's complement, values range from -128 to 127. + self.putx([0, ['XOUT: ' + str(b)]]) + + def handle_reg_0x01(self, b): + # YOUT: 8-bit y-axis acceleration output. + # Data is in 2's complement, values range from -128 to 127. + self.putx([0, ['YOUT: ' + str(b)]]) + + def handle_reg_0x02(self, b): + # STATUS: Orientation and shake status. + + # Bits [7:7]: INT + int_val = (b >> 7) & 1 + s = 'unchanged and no' if (int_val == 0) else 'changed or' + ann = 'INT = %d: Orientation %s shake event occured\n' % (int_val, s) + + # Bits[6:5]: SH[1:0] + sh = (((b >> 6) & 1) << 1) | ((b >> 5) & 1) + ann += 'SH[1:0] = %s: %s\n' % (bin(sh)[2:], status['sh'][sh]) + + # Bits[4:4]: TILT + tilt = (b >> 7) & 1 + s = '' if (tilt == 0) else 'not ' + ann += 'TILT = %d: Orientation measurement is %svalid\n' % (tilt, s) + + # Bits[3:2]: ORI[1:0] + ori = (((b >> 3) & 1) << 1) | ((b >> 2) & 1) + ann += 'ORI[1:0] = %s: %s\n' % (bin(ori)[2:], status['ori'][ori]) + + # Bits[1:0]: OR[1:0] + or_val = (((b >> 1) & 1) << 1) | ((b >> 0) & 1) + ann += 'OR[1:0] = %s: %s\n' % (bin(or_val)[2:], status['ori'][or_val]) + + # ann += 'b = %s\n' % (bin(b)) + + self.putx([0, [ann]]) + + def handle_reg_0x03(self, b): + # DETECTION: Powerdown, orientation and shake detection parameters. + # Note: This is a write-only register. + + # Bits [7:7]: PD + pd = (b >> 7) & 1 + s = 'Do not power down' if (int_val == 0) else 'Power down' + ann = 'PD = %d: %s the device\n' % (pd, s) + + # Bits [6:6]: SHM + shm = (b >> 6) & 1 + s = 'TODO' if (shm == 0) else 'TODO' + ann = 'SHM = %d: %s\n' % (pd, s) + + # TODO + # self.putx([0, ['TODO: DETECTION']]) + + # TODO: Fixup, this is copy-pasted from another PD. + 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' + self.block_start_sample = ss + elif self.state == 'GET SLAVE ADDR': + # Wait for an address write operation. + # TODO: We should only handle packets to the slave (0x2a/TODO). + if cmd != 'ADDRESS WRITE': + return + self.state = 'GET REG ADDR' + elif self.state == 'GET REG ADDR': + # Wait for a data write (master selects the slave register). + if cmd != 'DATA WRITE': + return + self.reg = databyte + self.state = 'WRITE RTC REGS' + elif self.state == 'WRITE RTC REGS': + # If we see a Repeated Start here, it's probably an RTC read. + if cmd == 'START REPEAT': + self.state = 'READ RTC REGS' + return + # Otherwise: Get data bytes until a STOP condition occurs. + if cmd == 'DATA WRITE': + handle_reg = getattr(self, 'handle_reg_0x%02x' % self.reg) + handle_reg(databyte) + self.reg += 1 + # TODO: Check for NACK! + elif cmd == 'STOP': + # TODO + self.state = 'IDLE' + else: + pass # TODO + elif self.state == 'READ RTC REGS': + # Wait for an address read operation. + # TODO: We should only handle packets to the RTC slave (0xa2/0xa3). + if cmd == 'ADDRESS READ': + self.state = 'READ RTC REGS2' + return + else: + pass # TODO + elif self.state == 'READ RTC REGS2': + if cmd == 'DATA READ': + handle_reg = getattr(self, 'handle_reg_0x%02x' % self.reg) + handle_reg(databyte) + self.reg += 1 + # TODO: Check for NACK! + elif cmd == 'STOP': + # TODO + self.state = 'IDLE' + else: + pass # TODO? + else: + raise Exception('Invalid state: %d' % self.state) + |