User manual

PoStep60 user manual
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8.2.2 Master read
Before read operation we shall always perform a Master write operation providing command for
read operation. After command is provided the Master read can be performed. In the Master read
operation PoStep response with multiple bytes of data. The data has to be properly interpreted by
the master.
STOP
I2C ADDRESS
R/W=1
A
BYTE0
A
BYTE1
A
…
BYTEn
A
END
From Master to PoStep driver
From PoStep driver to Master
8.3 PoStep60 I2C commands
8.3.1 0x01 - Loopback read
In a Master write operation master sends 0x01 command followed by 4 bytes. In a Master read
operation the 4 bytes from previous write operation are send back from the PoStep driver. The main
purpose of the command is to test a response of PoStep60 driver.
8.3.2 0x03 – Set Run/Sleep mode
To enable or disable (Run/Sleep) the driver Master shall write 0x03 command followed by one byte
of data – BYTE0. BYTE0 relates to Run/Sleep mode as follows:
Mode
BYTE0
Run
0xDA
Sleep
0x0F
8.3.3 0x04 – Set I2C address
Master writes 0x04 command followed by two bytes of data. BYTE0 shall be equal to current I2C
address (basic check before applying new address) and BYTE1 shall represent new I2C address.
8.3.4 0x05 – Set driver mode
Master writes 0x05 command followed by one BYTE of data.
BYTE
Mode
1
Default mode – external control
6
Auto run mode
NOTE!
Setting run over I2C overrides external enable signal. Similarly, external enable
overrides internal sleep signal.
CAUTION!
Please make sure to request Stop (8.3.38 0x5F – Stop) and Zero (8.3.37 0x5E – Set
zero) before changing driver mode to Auto run mode to prevent sudden motor
movement.