UI Robot Technology Co. Ltd.
M4120170509EN
Page 51
UIM241 Miniature Integrated Stepper Motor Controller(
Closed-loop
)
AA represents the ACK message, which is a repeat of the received instruction.
CC represents the status feedback, which is a description of current working status.
EE represents the error message.
Controller ID
The identification number of current controller in a network (also known as Node ID)
For UIM 241, Node ID is always 00.
Message ID
The property of the current message
For example, CC 00 A0 FF, where A0 denotes that there is a low level on sensor 1. For
details, please refer to following sections.
Data
Has a 7bits data structure. High is in front, and low is in the back.
In Figure 10-1 and 9-2, examples are shown on how to convert a set of 7bits data into 16bit
data and 32bit data.
Obviously, one 16bit data takes three 7bit data to represent, and one 32bit data takes five
7bit data.
Terminator
The end of a feedback message. UIM motion controller utilizes “FF” or “FE” as the
terminator. If terminator is “FF”, it means there is no follow-up message; if terminator is
“FE”, it means there has follow-up messages.
Note: there are two types of feedback that has NO message ID: ACK message and Motor
Status feedback (controller’s response to FBK instruction). Other messages could have
NO data, such as some real-time change notification messages.
Figure 10-1: Conversion from three 7bits message data to a 16bits data
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
16bit Binary Data
0 0 0 0 0 0 D15 D14
1
st
Byte
7
6
5
4
3
2
1
0
0 D13 D12 D11 D10 D9 D8 D7
2
nd
Byte
7
6
5
4
3
2
1
0
0
D6 D5 D4 D3 D2 D1 D0
3
rd
Byte
7
6
5
4
3
2
1
0
Data received (Hex): [XX] [XX] … [1
st
Byte] [2
nd
Byte] [3
rd
Byte] … [XX] [XX] [ FF ]
Receive sequence: earlier
later
