Loconet OPC_APM Message

Loconet OPC_APM message

Byte 0 is 0xD1, byte 5 is check_byte
Bit 7 of message bytes is always 0
This message is MagicRail private

variant	byte 1							byte 2							byte 3							byte 4
variant	6	5	4	3	2	1	0	6	5	4	3	2	1	0	6	5	4	3	2	1	0	6	5	4	3	2	1	0
general	A2	A1	A0	P3	P2	P1	P0	M1	M0	A7	A6	A5	A4	A3	D13	D12	D11	D10	D9	D8	D7	D6	D5	D4	D3	D2	D1	D0
drivers	A2	A1	A0	P3	P2	P1	P0	0	0	A7	A6	A5	A4	A3	limit even			RM	OC	RV	ON	limit odd			RM	OC	RV	ON

A7..A0 = device board number (not SV address)
P3..P0 = driver pair number
M1..M0 = mode, 0 displays driver status
D13..D0 = mode dependant data

limit in steps determined by processor type. 400ma for 648, 300ma for 18855
RM = reverser mode, polarity can be reversed to correct overcurrent
OC = overcurrent has caused shutdown
RV = polarity is reversed
ON = power is on