Serial protocol

Basic frame structure

Offset	Function
1 - 2	Frame header
3	Address
4 - 5	Data
6	Checksum

Checksums

The checksum is calculated as the byte sum (mod 256) of the frame address and data (see: AtyMain.java#L365-L379)

byte checksum = (byte)((address + data[0]) + data[1]); 

Frame headers

Header	Function
A5A5	Write data/params to BMS
5A5A	Read data/params from BMS
DBDB	Write data to the screen/main (?) board

Live data

Used in AtyParam2.java.

Bluetooth: Send 0xDBDB00000000 - Returns 140 bytes of data
BMS serial port: Send 0x5A5A00000000

Offset	Function	Type	Unit
0 - 3	Frame Header		0xAA 0x55 0xAA 0xFF
4 - 69	Voltage data		0.000 V
70 - 73	Current	int	0.0 A
74	Percentage of remaining battery	u8
75 - 78	Battery physical capacity	u32	.000000 AH
79 - 82	The remaining battery capacity	u32	.000000 AH
83 - 86	Total battery cycle capacity	u32	.000AH
87 - 90	Accumulated from boot time seconds	u32	S
91 - 102	Actual temperature	short	degree
103	Charge mos tube status flag	u8	(after analysis)
104	Discharge mos tube status flag	u8	(after analysis)
105	Balanced status flag	u8	(resolved below)
106 - 107	Tire length	u16	MM
108 - 109	The number of pulses per week	u16	N
110	Relay switch	u8	does not show
111 - 114	Current Power	int	W
115	Maximum number of monomer strings	u8	None
116 - 117	The highest monomer	u16	0.000V
118	Lowest monomer string	u8	None
119 - 120	Lowest monomer	u16	0.000V
121 - 122	Average	u16	0.000V
123	The number of effective batteries	u8	S
124 - 125	Detected discharge tube Voltage between D-S poles	u16	0.0V not to be displayed
126 - 127	Discharge MOS transistor driving voltage	u16	0.0V not display
128 - 129	Charging MOS tube driving voltage	u16	0.0V not display
130 - 131	When the detected current is 0, the comparator initial value Control equalization corresponds to 1 equalization	u16	is not displayed
132 - 135	(1 - 32 bits corresponds to 1 - 32 string equalization) corresponds to bit 1 displays the color at the corresponding voltage	u32
136 - 137	The system log is sent to the serial port data 0 - 4: Status 5 - 9: Battery number 10 - 14: Sequential order 15: Charge and discharge (1 discharge, 0 charge)	u16
136 - 137	System logs
138 - 139	Sum check	2 bytes

Checksum

The checksum is calculated as the sum of all data bytes at offsets 4 to 137 and will be verified as follows (see: BcService.java#L277-L286):

int expected = 0;
for (i = 4; i < 138; i++) {
    expected += data[i];
}

int checksum = (data[138] << 8) + data[139]; // big endian
if (checksum == expected) {
    // checksum valid
} else {
    // checksum invalid
}

Charge MOSFET status flag

Value	Type
0	Off
1	Open
2	Overvoltage protection
3	Over current protection
4	battery full
5	total overpressure
6	battery over temperature
7	power over temperature
8	Abnormal current
9	Balanced line dropped string
10	motherboard over temperature
13	Discharge tube abnormality
15	Manually closed

Discharge MOSFET status flag

Value	Type
0	Off
1	Open
2	Over-discharge protection
3	Over current protection
5	Total pressure undervoltage
6	Battery over temperature
7	Power over temperature
8	Abnormal current
9	Balanced line dropped string
10	Motherboard over temperature
11	Charge on
12	Short circuit protection
13	Discharge tube abnormality
14	Start exception
15	Manually closed

Balancing status flag

Value	Type
0	Off
1	Exceeds the limit equilibrium
2	Charge differential pressure balance
3	Balanced over temperature
4	Automatic equalization
10	Motherboard over temperature

Control addresses

Address	Type	Notes
247	Close BMS power
248	Current zeroing
249	Discharge MOS tube switch Forced to close the discharge tube	Data is 0
250	Charge MOS tube switch Forced shutdown charge officer	Data is 0
251	Change the parameter to iron lithium
252	The battery is automatically balanced
253	Factory Settings button
254	Reboot button
255	Apply button

Parameter addresses

AtyParam.java uses this parsing

Address	Type
1	Monomer over-voltage alarm voltage
2	Single undervoltage warning voltage
3	Single overvoltage protection voltage
4	Single undervoltage protection voltage
5	Monomer overvoltage recovery
6	Monomer undervoltage recovery
7	Total voltage overvoltage protection voltage
8	Total voltage undervoltage protection voltage
9	Charge Overcurrent Protection 000.0A
10	Charging Overcurrent Protection Delay Seconds
11	Discharge Overcurrent Protection
12	Discharge Overcurrent Protection Delay Seconds
13	Equilibrium voltage limit
14	Equilibrium starting voltage during charging
15	Equal pressure difference
16	Equilibrium current value (1-20)
17	System Voltage Reference
18	Current sensor range
19	Start Current (A)
20	Short Circuit Protection Current (A)
21	Short circuit protection delay (us)
22	No current automatic standby time (seconds)
23	Total voltage AD value is 0000 (4-digit integer) (is converted into the actual voltage value parameter)
24	Set the number of battery strings
25	Battery high temperature charge protection
26	Battery High Temperature Charge Recovery
27	Battery High Temperature Discharge Protection
28	Battery High Temperature Discharge Recovery
29	Power tube high temperature protection
30	Power tube high temperature recovery
31 - 32	Battery Physical Capacity .000 000AH (2 Spaces) (76 Low, 77 High)
33 - 34	remaining capacity .000 000AH (2 spaces) (78 low, 79 high)
35 - 36	Total circulation capacity .000AH (2 spaces) (80 low, 81 high)
41	Tire length
42	Number of pulses per week
51 - 74	Battery internal resistances
100	Runtime (70 - 71 two spaces)