AMIS-30624 AMI Semiconductor, Inc., AMIS-30624 Datasheet - Page 43

• Manufacturer Part Number: AMIS-30624
• Description: I2c Microstepping Motordriver
• Manufacturer: AMI Semiconductor, Inc.

AMIS-30624 I
16.6.1. Data Transfer Formats
16.6.1.1. Writing Data to AMIS-30624
When writing to AMIS-30624, the master-transmitter transmits to slave-receiver and the transfer direction is not changed. A complete
transmission consists of:
Some commands for the AMIS-30624 are supporting eight bytes of data, other commands are transmitting two bytes of data.
See Table 30.
16.6.1.2. Reading Data from AMIS-30624
When reading data from AMIS-30624 two transmissions are needed:
1) The first transmission consists of two bytes of data:
2) The second transmission consists of the slave address and the read bit. Then the master can read the data bits on the SDA line on
every rising edge of signal SCK. After each byte of data the master has to acknowledge correct data reception by pulling SDA LOW.
The last byte is not acknowledged by the master and therefore the slave knows the end of transmission.
Notes:
AMI Semiconductor – Apr. 2007, Rev 3.1, M-20664-003
www.amis.com
(1)
• Start condition
• The slave address (7-bit)
• Read/Write bit (‘0’ = write)
• Acknowledge bit
• Any further data bytes are followed by an acknowledge bit. The acknowledge bit is used to signal a correct reception of the
• Stop condition to finish the transmission
• The first byte contains the slave address and the write bit.
• The second byte contains the address of an internal register in the AMIS-30624. This internal register address is stored in the
data to the transmitter. In this case the AMIS-30624 pulls the SDA line to ‘0’. The AMIS-30624 reads the incoming data at SDA
on every rising edge of the SCK signal
circuit RAM.
Each byte is followed by an acknowledgment bit as indicated by the A or Ā in the sequence.
S
S
2
C Microstepping Motordriver
Master to AMIS-30624
Master to AMIS-30624
AMIS-30624 to Master
AMIS-30624 to Master
Slave Address
Slave Address
Figure 32: Master Reading Data from AMIS-30624: Second Transmission is Reading Data
Figure 31: Master Reading Data from AMIS-30624: First Transmission is Addressing
S
Slave Address
"0" = WRITE
"0" = WRITE
Figure 30: Master Writing Data to AMIS-30624
R/W
R/W
A
A
"0" = WRITE
R/W
S = Start condition
P = Stop condition
A = Acknowledge (SDA = LOW)
A = No Acknowledge (SDA = HIGH)
S = Start condition
P = Stop condition
A = Acknowledge (SDA = LOW)
A = No Acknowledge (SDA = HIGH)
A
43
Data
Data
Internal Address
N bytes + Acknowledge
N bytes + Acknowledge
A
A
PC20070219.5
A
Data
Data
P
PC20070219.3
PC20070219.3
A
A
P
P
Data Sheet