Differences

This shows you the differences between two versions of the page.

--- controllers [2023/06/04 18:50] – [Joystick] pulkomandy
+++ controllers [2023/06/05 19:59] (current) – [Checksum/keepalive] simer
@@ Line 161: / Line 161: @@
 ''0xb0 | (((A + B + 0x0f) & 0x0f) ^ 0x05)''
-where A and B are the two most recent nibbles sent by the console in 7x commands.
+where A and B are the two most recent lower nibbles sent by the console in 7x commands. If only one nibble has been sent, the other nibble in the algorithm will have 0 as its value. The console can also reset the previous state by sending a Bx command instead which otherwise works like a 7x command.
 The console must send the 7x commands, even if it ignores all the Bx replies from the controller. Without these commands, the controller eventually shuts down.