decoders/nes_gamepad/pd.py

   1 ##
   2 ## This file is part of the libsigrokdecode project.
   3 ##
   4 ## Copyright (C) 2019 Stephan Thiele <stephan.thiele@mailbox.org>
   5 ##
   6 ## This program is free software; you can redistribute it and/or modify
   7 ## it under the terms of the GNU General Public License as published by
   8 ## the Free Software Foundation; either version 2 of the License, or
   9 ## (at your option) any later version.
  10 ##
  11 ## This program is distributed in the hope that it will be useful,
  12 ## but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 ## GNU General Public License for more details.
  15 ##
  16 ## You should have received a copy of the GNU General Public License
  17 ## along with this program; if not, see <http://www.gnu.org/licenses/>.
  18 ##
  19
  20 import sigrokdecode as srd
  21
  22 class Decoder(srd.Decoder):
  23     api_version = 3
  24     id = 'nes_gamepad'
  25     name = 'NES gamepad'
  26     longname = 'Nintendo Entertainment System gamepad'
  27     desc = 'NES gamepad button states.'
  28     license = 'gplv2+'
  29     inputs = ['spi']
  30     outputs = []
  31     tags = ['Retro computing']
  32     options = (
  33         # Currently only the standard controller is supported. This might be
  34         # extended by special controllers like the Nintendo Zapper light gun.
  35         {'id': 'variant', 'desc': 'Gamepad variant',
  36             'default': 'Standard gamepad', 'values': ('Standard gamepad',)},
  37     )
  38     annotations = (
  39         ('button', 'Button state'),
  40         ('no-press', 'No button press'),
  41         ('not-connected', 'Gamepad unconnected')
  42     )
  43     annotation_rows = (
  44         ('buttons', 'Button states', (0,)),
  45         ('no-presses', 'No button presses', (1,)),
  46         ('not-connected-vals', 'Gamepad unconnected', (2,)),
  47     )
  48
  49     def __init__(self):
  50         self.reset()
  51
  52     def reset(self):
  53         self.variant = None
  54
  55     def start(self):
  56         self.out_ann = self.register(srd.OUTPUT_ANN)
  57         self.variant = self.options['variant']
  58
  59     def putg(self, ss, es, cls, text):
  60         self.put(ss, es, self.out_ann, [cls, [text]])
  61
  62     def handle_data(self, ss, es, value):
  63         if value == 0xff:
  64             self.putg(ss, es, 1, 'No button is pressed')
  65             return
  66
  67         if value == 0x00:
  68             self.putg(ss, es, 2, 'Gamepad is not connected')
  69             return
  70
  71         buttons = [
  72             'A',
  73             'B',
  74             'Select',
  75             'Start',
  76             'North',
  77             'South',
  78             'West',
  79             'East',
  80         ]
  81
  82         bits = '{:08b}'.format(value)
  83         text = [buttons[i] for i, b in enumerate(bits) if b == '0']
  84         text = ' + '.join(text)
  85         self.putg(ss, es, 0, text)
  86
  87     def decode(self, ss, es, data):
  88         ptype, _, _ = data
  89         if ptype == 'DATA':
  90             _, _, miso = data
  91             self.handle_data(ss, es, miso)
  92             return