OMY Unit Control Table

This document summarizes the control tables for both OMY units.
Shared concepts are explained once below, and unit-specific structures/descriptions are separated by tabs.

Control Table, Data, and Address

The control table is a collection of multiple data fields for device status and control.
Users can read specific data from the control table through READ Instruction Packets to understand the device status.
Users can also control the device by modifying specific data in the control table through WRITE Instruction Packets.
Address is a unique value used to access specific data in the control table via Instruction Packets.
To read or write device data, the address of the corresponding data must be specified in the Instruction Packet.
For detailed information about Packets, please refer to DYNAMIXEL Protocol 2.0.

INFO

Negative numbers follow the Two's complement rule. For detailed explanation of Two's complement, please refer to Wikipedia's Two's complement.

Area (EEPROM, RAM)

The control table is divided into EEPROM and RAM areas. The characteristics of each area are as follows:

Area	Description
EEPROM	Values in the EEPROM area are preserved even when power is turned off (Non-Volatile).
RAM	The RAM area is reset to default values each time power is applied (Volatile).

Size

Data size is determined by purpose, ranging from 1 to 4 bytes. When modifying data through Instruction Packets, please verify the size of the corresponding data.
Consecutive data of 2 bytes or more is recorded according to the Little Endian rule.

Access Permission

Control table data has two access attributes. RW allows both read and write access. R has a read-only attribute.
Data with read-only attributes cannot be changed via WRITE Instructions.
Read-only attributes (R) are primarily used for measurement or monitoring purposes, while read-write attributes (RW) are used for device control.

Initial Value

The default values for the EEPROM area listed in the manual are the initial settings (factory default settings) of the product.
The default value for the RAM area is the value set when power is applied to the device.

INFO

OMY BASE has an additional EEPROM write condition in operation: EEPROM values can only be changed when DXL Power Enable (512) is 0.

Control Table Structure

Address	Size (Byte)	Area	Data Name	Access	Initial Value	Range	Unit
0	2	EEPROM	Model Number	R	220	-	-
2	4	EEPROM	Model Information	R	-	-	-
6	1	EEPROM	Firmware Version	R	-	-	-
7	1	EEPROM	ID	R	200	-	-
8	1	EEPROM	Baud Rate (UART)	RW	9	0 ~ 9	-
9	1	EEPROM	Baud Rate (Bus)	RW	9	0 ~ 9	-
10	2	EEPROM	Regenerative Voltage Limit	RW	2900	500 ~ 3000	0.01 [V]
20	1	EEPROM	Table Sync ID 1	RW	255	0 ~ 255	-
21	1	EEPROM	Table Sync ID 2	RW	255	0 ~ 255	-
...	...	...	...	...	...	...	...
28	1	EEPROM	Table Sync ID 9	RW	255	0 ~ 255	-
29	1	EEPROM	Table Sync ID 10	RW	255	0 ~ 255	-
30	2	EEPROM	Table Sync Read Address 1	RW	0	0 ~ 1,023	-
32	2	EEPROM	Table Sync Read Address 2	RW	0	0 ~ 1,023	-
...	...	...	...	...	...	...	...
46	2	EEPROM	Table Sync Read Address 9	RW	0	0 ~ 1,023	-
48	2	EEPROM	Table Sync Read Address 10	RW	0	0 ~ 1,023	-
50	2	EEPROM	Table Sync Read Size 1	RW	0	0 ~ 1,024	-
52	2	EEPROM	Table Sync Read Size 2	RW	0	0 ~ 1,024	-
...	...	...	...	...	...	...	...
66	2	EEPROM	Table Sync Read Size 9	RW	0	0 ~ 1,024	-
68	2	EEPROM	Table Sync Read Size 10	RW	0	0 ~ 1,024	-
70	2	EEPROM	Table Sync Write Address 1	RW	0	0 ~ 1,023	-
72	2	EEPROM	Table Sync Write Address 2	RW	0	0 ~ 1,023	-
...	...	...	...	...	...	...	...
86	2	EEPROM	Table Sync Write Address 9	RW	0	0 ~ 1,023	-
88	2	EEPROM	Table Sync Write Address 10	RW	0	0 ~ 1,023	-
90	2	EEPROM	Table Sync Write Size 1	RW	0	0 ~ 1,024	-
92	2	EEPROM	Table Sync Write Size 2	RW	0	0 ~ 1,024	-
...	...	...	...	...	...	...	...
106	2	EEPROM	Table Sync Write Size 9	RW	0	0 ~ 1,024	-
108	2	EEPROM	Table Sync Write Size 10	RW	0	0 ~ 1,024	-
112	2	EEPROM	Indirect Address 1	RW	816	0 ~ 1,023	-
114	2	EEPROM	Indirect Address 2	RW	817	0 ~ 1,023	-
...	...	...	...	...	...	...	...
500	2	EEPROM	Indirect Address 195	RW	1010	0 ~ 1,023	-
502	2	EEPROM	Indirect Address 196	RW	1011	0 ~ 1,023	-
512	1	RAM	DXL Power Enable	RW	0	0 ~ 1	-
513	1	RAM	Regenerative Voltage Enable	RW	0	0 ~ 1	-
514	1	RAM	Table Sync Enable	RW	0	0 ~ 1	-
515	1	RAM	LED Red	RW	0	0 ~ 255	-
516	1	RAM	LED Green	RW	0	0 ~ 255	-
517	1	RAM	LED Blue	RW	0	0 ~ 255	-
518	1	RAM	Status	RW	0	0 ~ 255	-
519	1	RAM	EMG Power Off	RW	0	0 ~ 1	-
520	2	RAM	Realtime Tick	R	0	0 ~ 32,767	1 [ms]
522	2	RAM	Present Input Voltage	R	-	-	0.01 [V]
556	1	RAM	Status Return Level	RW	2	0 ~ 2	-
560	1	RAM	Table Sync Read Data 1	R	0	-	-
561	1	RAM	Table Sync Read Data 2	R	0	-	-
...	...	...	...	...	...	...	...
686	1	RAM	Table Sync Read Data 127	R	0	-	-
687	1	RAM	Table Sync Read Data 128	R	0	-	-
688	1	RAM	Table Sync Write Data 1	RW	0	0 ~ 255	-
689	1	RAM	Table Sync Write Data 2	RW	0	0 ~ 255	-
...	...	...	...	...	...	...	...
814	1	RAM	Table Sync Write Data 127	RW	0	0 ~ 255	-
815	1	RAM	Table Sync Write Data 128	RW	0	0 ~ 255	-
816	1	RAM	Indirect Data 1	RW	0	0 ~ 255	-
817	1	RAM	Indirect Data 2	RW	0	0 ~ 255	-
...	...	...	...	...	...	...	...
1010	1	RAM	Indirect Data 195	RW	0	0 ~ 255	-
1011	1	RAM	Indirect Data 196	RW	0	0 ~ 255	-

Control Table Description

Model Number (0)

The model number of the device.

Model Information (2)

Additional information about the device model.

Firmware Version (6)

The firmware version of the device.

ID (7)

A unique number used to identify the device via Instruction Packets. For BASE, the ID is fixed to 200 (0xC8) (read-only) and does not respond to Broadcast ID 254 (0xFE).

INFO

If the Instruction Packet ID is not 200 (0xC8), the unit operates in Bypass mode and communicates with DYNAMIXELs connected to the DYNAMIXEL port.

Baud Rate (UART) (8)

Communication speed between host controller (e.g. Raspberry Pi) and BASE unit.

WARNING

When communicating with a PC via the Debug Port (USB-C), communication with the host controller is not available.

Baud Rate (Bus) (9)

Communication speed for the DYNAMIXEL bus.

INFO

Communication is only reliable when the baud rate error is 3% or less.

Regenerative Voltage Limit / Regenerative Voltage Enable (10 / 513)

Limits voltage rise from regeneration when DYNAMIXELs decelerate or back-drive.

WARNING

Set Regenerative Voltage Limit higher than the power supply output voltage. Lower values may damage internal resistor circuitry.

Table Sync (ID 20-29, Addr/Size 30-108, Enable 514, Read/Write Data 560-815)

BASE maps connected DYNAMIXEL control tables into local read/write sync buffers with per-ID slots (up to 10).

INFO

Example: IDs 1 and 2, Present Position read / Goal Position write - set Read Address 552, Write Address 532, Read Size 4, Write Size 4, then enable Table Sync.

Indirect Address / Indirect Data (112-502 / 816-1011)

Maps specific control table addresses into Indirect Data. For multi-byte items, assign all consecutive bytes.

DXL Power Enable (512)

Supplies power to connected DYNAMIXELs.

LED Red / Green / Blue (515-517)

RGB LED intensity (0-255 per channel).

Status (518)

Bit	Name	Description
3	Overload Error	Regenerative resistor overload
2	Dynamixel Error	DYNAMIXEL error state
1	Communication Error	Communication error
0	Emergency	Emergency (EMG) state

EMG Power Off (519)

Controls whether DYNAMIXEL power is cut when EMG is active.

Realtime Tick (520)

Device time counter for timestamps. Unit: 1 [ms], range 0 ~ 32,767, then wraps to 0.

Present Input Voltage (522)

Current supply voltage to BASE device (0.01 [V] per LSB).

Status Return Level (556)

Determines which Instructions return a Status Packet (0: PING only, 1: PING + READ, 2: all).