> 1 0001 XXX 0 XXXXXXX (88+) PING Ping `X' (please Pong `X')
> 1 0010 RRR E RRR... (90+) POLARITY Set polarity
> 1 0011 000 0 MMMMMMM (98+) WATCHDOG W'dog reset, t/o <M*16>ms from now
- > 0 0100 001 (21) ON Power on
- > 0 0100 000 (20) OFF Power off
+ > 0 0010 001 (11) ON Power on
+ > 0 0010 000 (10) OFF Power off
- > 00000000 CRASHED Acknowledge panic, go to readout mode
- > 00000001 ACKSERERR RS232 framing or overrung (panic'd)
+;> 00000000 CRASHED Acknowledge panic, go to readout mode
+;> 00001002 (0a) TELLMODE Confirm mode - say HELLO or CRASHED
+; if crashed, undoes the effect of ack
; In crash readout mode:
;
; 00000000 MS Select crash readout mode if not already
; Reset crash readout pointer to 0
;
+; 00001000 Acknowledge RS232 framing error or overrun
+; 00001001 Reboot
+;
; 1vvvvvvv M Prepare byte 0vvvvvvv for transmission to the slave
;
-; 0000nnnn M (n>0) prepare to receive nnnn bytes from slave
+; 00000nnn M (n>0) prepare to receive nnnn bytes from slave
; 0001nnnn M (n>0) transmit nnnn bytes of our own from the
; readout pointer
;
(User Fault indicator lit)
+If OFF is issued in the first 500ms following a short circuit, it will
+be ignored; if the short circuit persists, OFF during the following
+period will go to the `Track and CDU disabled' state without sending
+FIXED.
+
POINTS and CDU
--------------
is recharging <----POINTED---- Point is changing
+Note that OFF will turn the CDU off, and a short circuit (FAULT) will
+turn it off 500ms later (this delay avoids losing races where the host
+sends a point change instruction just before a short happens).
+
PING and PONG
-------------