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Talk:Wiimote/Extension Controllers/Drawsome Tablet (view source)
Revision as of 21:16, 18 February 2017
, 21:16, 18 February 2017→Tablet Notes
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[[User:Acamilo|Acamilo]] ([[User talk:Acamilo|talk]]) 23:43, 16 February 2017 (CET)
[[User:Acamilo|Acamilo]] ([[User talk:Acamilo|talk]]) 23:43, 16 February 2017 (CET)
+
+
+Good news. I'm getting data from the tablet.
+
+I started it up the way the wii did after using a analyzer on the i2c bus to see what the wii did.
+
+A log of i2c comms between a wiimote and the wii running the included sw CD.
+ <nowiki>
+// unenc init
+a4 w f0 55
+a4 w fb 00
+
+Read ID Bytes
+a4 w fa
+a5 r ff 00 a4 20 00 13
+
+// Enter enc mode
+a4 w f0 aa
+
+// write 16 byte key
+a4 w 40 e0 7d e0 7d e0 7d
+a4 w 46 e0 7d e0 7d 38 54
+a4 w 4c bb 79 01 43
+
+// Read Cal Data
+a4 w 20
+a5 r a2 b2 89 40 0f 1f 39 f0
+a5 r a2 b2 89 40 0f 1f 39 f0
+
+a4 w 30
+a5 r a2 b2 89 40 0f 1f 39 f0
+a5 r a2 b2 89 40 0f 1f 39 f0
+
+// Read inputs
+a4 w 00
+
+a5 r a3 b1 8a 41 0e 5e 38 f3
+a5 r a3 b1 8a 41 0e 1e 38 f3
+
+many more 00 reads
+
+????
+a4 w fb 01
+
+many more 00 reads
+</nowiki>
+
+
+Looks like 3 things need to happen to make this tablet work.
+You need to explicitly enable encrypted mode and send a full 16 bytes of key or it will return FFs. Additionally, You need to write 01 to FB.
+
+I wrote 16 zeros for the key and decrypted the data with (e ^ 0x97)+0x97 and I'm getting bytes that make sense.
+
+So far I've figured out that bit7 (index zero) of byte 5 (index zero) is a flag for detecting a pen in range. bits 2 to 0 of byte 5 are the MSbits of a pressure value. Additionally, bits 5 to 0 of bytes 1 and 3 are the upper 6 bits of X and Y pen positions respectively.
+
+I'm gonna keep poking at this.
+[[User:Acamilo|Acamilo]] ([[User talk:Acamilo|talk]]) 20:16, 18 February 2017 (CET)