ps2: Added mouse and keyboard stacked decoders

Mouse decoder interprets the 3-byte packets for movement and clicking, but
ignores the configuration commands from the host.
Keyboard decoder interprets press and release messages for each key but does not keep track of state (capslock, shift, etc).

decoders/ps2_keyboard/__init__.py

@@ -0,0 +1,25 @@
+##
+## This file is part of the libsigrokdecode project.
+##
+## Copyright (C) 2023 Marshal Horn <[email protected]>
+##
+## 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, see <http://www.gnu.org/licenses/>.
+##
+
+'''
+This protocol decoder can decode PS/2 keyboard commands.
+It should be stacked on the PS/2 packet decoder.
+'''
+
+from .pd import Decoder

decoders/ps2_keyboard/pd.py

@@ -0,0 +1,93 @@
+##
+## This file is part of the libsigrokdecode project.
+##
+## Copyright (C) 2023 Marshal Horn <[email protected]>
+##
+## 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, see <http://www.gnu.org/licenses/>.
+##
+
+import sigrokdecode as srd
+from .sc import key_decode
+
+class Ps2Packet:
+    def __init__(self, val, host=False, pok=False, ack=False):
+        self.val  = val     #byte value
+        self.host = host    #Host transmissions
+        self.pok  = pok     #Parity ok
+        self.ack  = ack     #Acknowlege ok for host transmission.
+
+class Ann:
+    PRESS,RELEASE,ACK = range(3)
+
+class Decoder(srd.Decoder):
+    api_version = 3
+    id = 'keyboard'
+    name = 'PS/2 Keyboard'
+    longname = 'PS/2 Keyboard'
+    desc = 'PS/2 keyboard interface.'
+    license = 'gplv2+'
+    inputs = ['ps2_packet']
+    outputs = []
+    tags = ['PC']
+    binary = (
+        ('Keys', 'Key presses'),
+    )
+    annotations = (
+        ('Press', 'Key pressed'),
+        ('Release', 'Key released'),
+        ('Ack', 'Acknowledge'),
+    )
+    annotation_rows = (
+        ('keys', 'key presses and releases',(0,1,2)),
+    )
+
+    def __init__(self):
+        self.reset()
+
+    def reset(self):
+        self.sw = 0 #for switch statement
+        self.ann = Ann.PRESS #defualt to keypress
+        self.extended = False
+
+    def start(self):
+        self.out_binary = self.register(srd.OUTPUT_BINARY)
+        self.out_ann = self.register(srd.OUTPUT_ANN)
+
+    def decode(self,startsample,endsample,data):
+        if data.host:
+            # Ignore host commands or interrupted keycodes
+            self.reset()
+            return
+        if self.sw < 1:
+            self.ss = startsample
+            self.sw = 1
+        if self.sw < 2:
+            if data.val == 0xF0: #Break code
+                self.ann = Ann.RELEASE
+                return
+            elif data.val == 0xE0: #Extended character
+                self.extended = True
+                return
+            elif data.val == 0xFA: #Acknowledge code
+                c = ['Acknowledge','ACK']
+                self.ann = Ann.ACK
+                self.sw = 4
+        if self.sw < 3:
+            c = key_decode(data.val, self.extended)
+
+        self.put(self.ss,endsample,self.out_ann,[self.ann,c])
+        if self.ann == Ann.PRESS:
+            self.put(self.ss,endsample,self.out_binary,[0,c[-1].encode('UTF-8')])
+        self.reset()
+

decoders/ps2_keyboard/sc.py

@@ -0,0 +1,99 @@
+#A list of scancodes for the PS2 keyboard
+ext = { 
+    0x1F:'L Sup',
+    0x14:'R Ctrl',
+    0x27:'R Sup',
+    0x11:'R Alt',
+    0x2F:'Menu',
+    0x12:'PrtScr',
+    0x7C:'SysRq',
+    0x70:'Insert',
+    0x6C:'Home',
+    0x7D:'Pg Up',
+    0x71:'Delete',
+    0x69:'End',
+    0x7A:'Pg Dn',
+    0x75:['Up arrow','^'],
+    0x6B:['Left arrow','Left','<-'],
+    0x74:['Right arrow','Right','->'],
+    0x72:['Down arrow','Down','v'],
+    0x4A:['KP /','/'],
+    0x5A:['KP Ent','\n'], 
+}
+
+std = { 
+    0x1C:'A',
+    0x32:'B',
+    0x21:'C',
+    0x23:'D',
+    0x24:'E',
+    0x2B:'F',
+    0x34:'G',
+    0x33:'H',
+    0x43:'I',
+    0x3B:'J',
+    0x42:'K',
+    0x4B:'L',
+    0x3A:'M',
+    0x31:'N',
+    0x44:'O',
+    0x4D:'P',
+    0x15:'Q',
+    0x2D:'R',
+    0x1B:'S',
+    0x2C:'T',
+    0x3C:'U',
+    0x2A:'V',
+    0x1D:'W',
+    0x22:'X',
+    0x35:'Y',
+    0x1A:'Z',
+    0x45:'0)',
+    0x16:'1!',
+    0x1E:'2@',
+    0x26:'3#',
+    0x25:'4$',
+    0x2E:'5%',
+    0x36:'6^',
+    0x3D:'7&',
+    0x3E:'8*',
+    0x46:'9(',
+    0x0E:'`~',
+    0x4E:'-_',
+    0x55:'=+',
+    0x5D:'\|',
+    0x66:'Backsp',
+    0x29:['Space',' '],
+    0x0D:['Tab','\t'],
+    0x58:'CapsLk',
+    0x12:'L Shft',
+    0x14:'L Ctrl',
+    0x11:'L Alt',
+    0x59:'R Shft',
+    0x5A:['Enter','\n'],
+    0x76:'Esc',
+    0x5:'F1',
+    0x6:'F2',
+    0x4:'F3',
+    0x0C:'F4',
+    0x3:'F5',
+    0x0B:'F6',
+    0x83:'F7',
+    0x0A:'F8',
+    0x1:'F9',
+    0x9:'F10',
+    0x78:'F11',
+    0x7:'F12',
+    0x7E:'ScrLck',
+}
+
+
+def key_decode(code, extended):
+    try:
+        c = ext[code] if extended else std[code]
+    except KeyError:
+        fs = '[E0%0X]' if extended else '[%0X]'
+        c = fs % code
+    if not isinstance(0,list):
+        c = [c]
+    return c

decoders/ps2_mouse/__init__.py

@@ -0,0 +1,25 @@
+##
+## This file is part of the libsigrokdecode project.
+##
+## Copyright (C) 2023 Marshal Horn <[email protected]>
+##
+## 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, see <http://www.gnu.org/licenses/>.
+##
+
+'''
+This protocol decoder can decode PS/2 mouse commands.
+It should be stacked on the PS/2 packet decoder.
+'''
+
+from .pd import Decoder

decoders/ps2_mouse/pd.py

@@ -0,0 +1,124 @@
+##
+## This file is part of the libsigrokdecode project.
+##
+## Copyright (C) 2023 Marshal Horn <[email protected]>
+##
+## 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, see <http://www.gnu.org/licenses/>.
+##
+
+import sigrokdecode as srd
+
+class Ps2Packet:
+    def __init__(self, val, host=False, pok=False, ack=False):
+        self.val  = val     #byte value
+        self.host = host    #Host transmissions
+        self.pok  = pok     #Parity ok
+        self.ack  = ack     #Acknowlege ok for host transmission.
+
+class Decoder(srd.Decoder):
+    api_version = 3
+    id = 'mouse'
+    name = 'PS/2 Mouse'
+    longname = 'PS/2 Mouse'
+    desc = 'PS/2 mouse interface.'
+    license = 'gplv2+'
+    inputs = ['ps2_packet']
+    outputs = []
+    tags = ['PC']
+    binary = (
+        ('bytes', 'Bytes without explanation'),
+        ('movement', 'Explanation of mouse movement and clicks'),
+    )
+    annotations = (
+        ('Movement', 'Mouse movement packets'),
+    )
+    annotation_rows = (
+        ('mov', 'Mouse Movement',(0,)),
+    )
+
+    def __init__(self):
+        self.reset()
+
+    def reset(self):
+        self.packets = []
+        self.es = 0
+        self.ss = 0
+
+    def start(self):
+        self.out_binary = self.register(srd.OUTPUT_BINARY)
+        self.out_ann = self.register(srd.OUTPUT_ANN)
+
+    def metadata(self,key,value):
+        if key == srd.SRD_CONF_SAMPLERATE:
+            self.samplerate = value
+
+    def mouse_movement(self):
+        if len(self.packets) >= 3:
+            if not self.packets[0].host:
+                msg = ''
+                [flags,x,y] = [p.val for p in self.packets[:3]]
+                if flags & 1:
+                    msg += 'L'
+                if flags & 2:
+                    msg += 'M'
+                if flags & 4:
+                    msg += 'R'
+                if flags & 0x10:
+                    x = x-256
+                if flags & 0x20:
+                    y = y-256
+                if x != 0:
+                    msg += ' X%+d' % x
+                if flags & 0x40:
+                    msg += '!!'
+                if y != 0:
+                    msg += ' Y%+d' % y
+                if flags & 0x80:
+                    msg += '!!'
+                if msg == '':
+                    msg = 'No Movement'
+                ustring = ('\n' + msg).encode('UTF-8')
+                self.put(self.ss,self.es,self.out_binary, [1,ustring] )
+                self.put(self.ss,self.es,self.out_ann, [0,[msg]] )
+
+
+    def print_packets(self):
+        self.mouse_movement()
+        tag = "Host: " if self.packets[-1].host else "Mouse:"
+        octets = ' '.join(["%02X" % x.val for x in self.packets])
+        unicode_string = ("\n"+tag+" "+octets).encode('UTF-8')
+        self.put(self.ss,self.es,self.out_binary, [0,unicode_string] )
+        self.reset()
+
+    def mouse_ack(self,ss,es):
+        self.put(ss,es,self.out_binary, [0,b' ACK'] )
+
+    def decode(self,startsample,endsample,data):
+        if len(self.packets) == 0:
+            self.ss = startsample
+        elif data.host != self.packets[-1].host:
+            self.print_packets() 
+            self.ss = startsample #Packets were cleared, need to set startsample again
+            if data.val == 0xFA and not data.host:
+                #Special case: acknowledge byte from mouse
+                self.mouse_ack(startsample,endsample)
+                self.reset()
+                return
+
+        self.packets.append(data)
+        self.es = endsample
+        #Mouse streaming packets are in 3s
+        #Timing is not guaranteed because host can hold the clock at any point
+        if len(self.packets)>2:
+            self.print_packets()