## ## This file is part of the libsigrokdecode project. ## ## Copyright (C) 2012 Uwe Hermann ## ## 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 # Definitions of various bits in MXC6225XU registers. status = { # SH[1:0] 'sh': { 0b00: 'none', 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', }, # SHTH[1:0] 'shth': { 0b00: '0.5g', 0b01: '1.0g', 0b10: '1.5g', 0b11: '2.0g', }, # SHC[1:0] 'shc': { 0b00: '16', 0b01: '32', 0b10: '64', 0b11: '128', }, # ORC[1:0] 'orc': { 0b00: '16', 0b01: '32', 0b10: '64', 0b11: '128', }, } 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 = [ ['Text', 'Human-readable text'], ] def __init__(self, **kwargs): self.state = 'IDLE' def start(self): # 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: %d' % 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: %d' % 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: Shake event: %s\n' % \ (bin(sh)[2:], status['sh'][sh]) # Bits[4:4]: TILT tilt = (b >> 4) & 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 (pd == 0) else 'Power down' ann = 'PD = %d: %s the device (into a low-power state)\n' % (pd, s) # Bits[6:6]: SHM shm = (b >> 6) & 1 ann = 'SHM = %d: Set shake mode to %d\n' % (shm, shm) # Bits[5:4]: SHTH[1:0] shth = (((b >> 5) & 1) << 1) | ((b >> 4) & 1) ann += 'SHTH[1:0] = %s: Set shake threshold to %s\n' \ % (bin(shth)[2:], status['shth'][shth]) # Bits[3:2]: SHC[1:0] shc = (((b >> 3) & 1) << 1) | ((b >> 2) & 1) ann += 'SHC[1:0] = %s: Set shake count to %s readings\n' \ % (bin(shc)[2:], status['shc'][shc]) # Bits[1:0]: ORC[1:0] orc = (((b >> 1) & 1) << 1) | ((b >> 0) & 1) ann += 'ORC[1:0] = %s: Set orientation count to %s readings\n' \ % (bin(orc)[2:], status['orc'][orc]) self.putx([0, [ann]]) # TODO: Fixup, this is copy-pasted from another PD. # TODO: Handle/check the ACKs/NACKs. 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(?) 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 REGS' elif self.state == 'WRITE REGS': # If we see a Repeated Start here, it's a multi-byte read. if cmd == 'START REPEAT': self.state = 'READ 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 REGS': # Wait for an address read operation. # TODO: We should only handle packets to the slave(?) if cmd == 'ADDRESS READ': self.state = 'READ REGS2' return else: pass # TODO elif self.state == 'READ 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: %s' % self.state)