## ## This file is part of the libsigrokdecode project. ## ## Copyright (C) 2014 Jens Steinhauser ## ## 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 ## import sigrokdecode as srd class ChannelError(Exception): pass regs = { # addr: ('name', size) 0x00: ('CONFIG', 1), 0x01: ('EN_AA', 1), 0x02: ('EN_RXADDR', 1), 0x03: ('SETUP_AW', 1), 0x04: ('SETUP_RETR', 1), 0x05: ('RF_CH', 1), 0x06: ('RF_SETUP', 1), 0x07: ('STATUS', 1), 0x08: ('OBSERVE_TX', 1), 0x09: ('RPD', 1), 0x0a: ('RX_ADDR_P0', 5), 0x0b: ('RX_ADDR_P1', 5), 0x0c: ('RX_ADDR_P2', 1), 0x0d: ('RX_ADDR_P3', 1), 0x0e: ('RX_ADDR_P4', 1), 0x0f: ('RX_ADDR_P5', 1), 0x10: ('TX_ADDR', 5), 0x11: ('RX_PW_P0', 1), 0x12: ('RX_PW_P1', 1), 0x13: ('RX_PW_P2', 1), 0x14: ('RX_PW_P3', 1), 0x15: ('RX_PW_P4', 1), 0x16: ('RX_PW_P5', 1), 0x17: ('FIFO_STATUS', 1), 0x1c: ('DYNPD', 1), 0x1d: ('FEATURE', 1), } class Decoder(srd.Decoder): api_version = 2 id = 'nrf24l01' name = 'nRF24L01(+)' longname = 'Nordic Semiconductor nRF24L01/nRF24L01+' desc = '2.4GHz transceiver chip.' license = 'gplv2+' inputs = ['spi'] outputs = ['nrf24l01'] annotations = ( # Sent from the host to the chip. ('cmd', 'Commands sent to the device'), ('tx-data', 'Payload sent to the device'), # Returned by the chip. ('register', 'Registers read from the device'), ('rx-data', 'Payload read from the device'), ('warning', 'Warnings'), ) ann_cmd = 0 ann_tx = 1 ann_reg = 2 ann_rx = 3 ann_warn = 4 annotation_rows = ( ('commands', 'Commands', (ann_cmd, ann_tx)), ('responses', 'Responses', (ann_reg, ann_rx)), ('warnings', 'Warnings', (ann_warn,)), ) def __init__(self, **kwargs): self.next() def start(self): self.out_ann = self.register(srd.OUTPUT_ANN) def warn(self, pos, msg): '''Put a warning message 'msg' at 'pos'.''' self.put(pos[0], pos[1], self.out_ann, [self.ann_warn, [msg]]) def putp(self, pos, ann, msg): '''Put an annotation message 'msg' at 'pos'.''' self.put(pos[0], pos[1], self.out_ann, [ann, [msg]]) def next(self): '''Resets the decoder after a complete command was decoded.''' # 'True' for the first byte after CS went low. self.first = True # The current command, and the minimum and maximum number # of data bytes to follow. self.cmd = None self.min = 0 self.max = 0 # Used to collect the bytes after the command byte # (and the start/end sample number). self.mb = [] self.mb_s = -1 self.mb_e = -1 def mosi_bytes(self): '''Returns the collected MOSI bytes of a multi byte command.''' return [b[0] for b in self.mb] def miso_bytes(self): '''Returns the collected MISO bytes of a multi byte command.''' return [b[1] for b in self.mb] def decode_command(self, pos, b): '''Decodes the command byte 'b' at position 'pos' and prepares the decoding of the following data bytes.''' c = self.parse_command(b) if c is None: self.warn(pos, 'unknown command') return self.cmd, self.dat, self.min, self.max = c if self.cmd in ('W_REGISTER', 'ACTIVATE'): # Don't output anything now, the command is merged with # the data bytes following it. self.mb_s = pos[0] else: self.putp(pos, self.ann_cmd, self.format_command()) def format_command(self): '''Returns the label for the current command.''' if self.cmd == 'R_REGISTER': reg = regs[self.dat][0] if self.dat in regs else 'unknown register' return 'Cmd R_REGISTER "{}"'.format(reg) else: return 'Cmd {}'.format(self.cmd) def parse_command(self, b): '''Parses the command byte. Returns a tuple consisting of: - the name of the command - additional data needed to dissect the following bytes - minimum number of following bytes - maximum number of following bytes ''' if (b & 0xe0) in (0b00000000, 0b00100000): c = 'R_REGISTER' if not (b & 0xe0) else 'W_REGISTER' d = b & 0x1f m = regs[d][1] if d in regs else 1 return (c, d, 1, m) if b == 0b01010000: # nRF24L01 only return ('ACTIVATE', None, 1, 1) if b == 0b01100001: return ('R_RX_PAYLOAD', None, 1, 32) if b == 0b01100000: return ('R_RX_PL_WID', None, 1, 1) if b == 0b10100000: return ('W_TX_PAYLOAD', None, 1, 32) if b == 0b10110000: return ('W_TX_PAYLOAD_NOACK', None, 1, 32) if (b & 0xf8) == 0b10101000: return ('W_ACK_PAYLOAD', b & 0x07, 1, 32) if b == 0b11100001: return ('FLUSH_TX', None, 0, 0) if b == 0b11100010: return ('FLUSH_RX', None, 0, 0) if b == 0b11100011: return ('REUSE_TX_PL', None, 0, 0) if b == 0b11111111: return ('NOP', None, 0, 0) def decode_register(self, pos, ann, regid, data): '''Decodes a register. pos -- start and end sample numbers of the register ann -- is the annotation number that is used to output the register. regid -- may be either an integer used as a key for the 'regs' dictionary, or a string directly containing a register name.' data -- is the register content. ''' if type(regid) == int: # Get the name of the register. if regid not in regs: self.warn(pos, 'unknown register') return name = regs[regid][0] else: name = regid # Multi byte register come LSByte first. data = reversed(data) if self.cmd == 'W_REGISTER' and ann == self.ann_cmd: # The 'W_REGISTER' command is merged with the following byte(s). label = '{}: {}'.format(self.format_command(), name) else: label = 'Reg {}'.format(name) self.decode_mb_data(pos, ann, data, label, True) def decode_mb_data(self, pos, ann, data, label, always_hex): '''Decodes the data bytes 'data' of a multibyte command at position 'pos'. The decoded data is prefixed with 'label'. If 'always_hex' is True, all bytes are decoded as hex codes, otherwise only non printable characters are escaped.''' if always_hex: def escape(b): return '{:02X}'.format(b) else: def escape(b): c = chr(b) if not str.isprintable(c): return '\\x{:02X}'.format(b) return c data = ''.join([escape(b) for b in data]) text = '{} = "{}"'.format(label, data) self.putp(pos, ann, text) def finish_command(self, pos): '''Decodes the remaining data bytes at position 'pos'.''' if self.cmd == 'R_REGISTER': self.decode_register(pos, self.ann_reg, self.dat, self.miso_bytes()) elif self.cmd == 'W_REGISTER': self.decode_register(pos, self.ann_cmd, self.dat, self.mosi_bytes()) elif self.cmd == 'R_RX_PAYLOAD': self.decode_mb_data(pos, self.ann_rx, self.miso_bytes(), 'RX payload', False) elif (self.cmd == 'W_TX_PAYLOAD' or self.cmd == 'W_TX_PAYLOAD_NOACK'): self.decode_mb_data(pos, self.ann_tx, self.mosi_bytes(), 'TX payload', False) elif self.cmd == 'W_ACK_PAYLOAD': lbl = 'ACK payload for pipe {}'.format(self.dat) self.decode_mb_data(pos, self.ann_tx, self.mosi_bytes(), lbl, False) elif self.cmd == 'R_RX_PL_WID': msg = 'Payload width = {}'.format(self.mb[0][1]) self.putp(pos, self.ann_reg, msg) elif self.cmd == 'ACTIVATE': self.putp(pos, self.ann_cmd, self.format_command()) if self.mosi_bytes()[0] != 0x73: self.warn(pos, 'wrong data for "ACTIVATE" command') def decode(self, ss, es, data): ptype, data1, data2 = data if ptype == 'CS-CHANGE': if data1 == 0 and data2 == 1: # Rising edge, the complete command is transmitted, process # the bytes that were send after the command byte. if self.cmd: # Check if we got the minimum number of data bytes # after the command byte. if len(self.mb) < self.min: self.warn((ss, ss), 'missing data bytes') elif self.mb: self.finish_command((self.mb_s, self.mb_e)) self.next() elif ptype == 'DATA': mosi, miso = data1, data2 pos = (ss, es) if miso is None or mosi is None: raise ChannelError('Both MISO and MOSI pins required.') if self.first: self.first = False # First MOSI byte is always the command. self.decode_command(pos, mosi) # First MISO byte is always the status register. self.decode_register(pos, self.ann_reg, 'STATUS', [miso]) else: if not self.cmd or len(self.mb) >= self.max: self.warn(pos, 'excess byte') else: # Collect the bytes after the command byte. if self.mb_s == -1: self.mb_s = ss self.mb_e = es self.mb.append((mosi, miso))