FT201XQ-R FTDI, FT201XQ-R Datasheet - Page 32

• Manufacturer Part Number: FT201XQ-R
• Description: USB Interface IC USB to I2C IC QFN-16
• Manufacturer: FTDI

Specifications of FT201XQ-R

• Rohs: yes
• Product: USB 2.0
• Data Rate: 12 Mbps, 480 Mbps
• Interface Type: I2C, USB
• Operating Supply Voltage: 2.97 V to 5.5 V
• Operating Supply Current: 6.4 mA to 8.65 mA
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: QFN-16
• Tradename: X-Chip

Figure 9.2: Data transfers with 7-bit and 10-bit addressing modes
Flow Control when Reading
When reading data, it is important to know if there is data available to read over I
is valid. There are three methods by which to check whether the data being read is valid.
Figure 9.3: Checking the Data Available Count
Flow Control when Writing
When writing data (data going from I
space available and if the FT-X accepted the byte written. There are two methods by which to check
whether space is available.
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-
-
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Checking the I2C_TXE# line, which indicates whether the transmit buffer is empty. This signal
can be mapped to the CBUS pins. This line does not indicate the number of bytes available. If the
line is asserted, there are one or more bytes in the transmit buffer. Note that the Transmit buffer
is the buffer which holds data which has come from the host computer and is going to be read by
the external I
Do a read over I
acknowledges the address phase. The FT-X will NAK the address phase if there is no data to read.
If bursting data, then there is not an address phase for each byte. In this case, it is not possible
to tell when the buffer has emptied and therefore when you are no longer reading valid bytes. In
this case, a Data Available check can be carried out first. If the byte after the general call address
is 0x0C (0000 1100), the FT-X returns the Data Available Count to indicate the number of bytes
available for burst read. Please also refer to section 9.3. Note that because this returns a single
byte, the maximum value is 0xFF, and so a value of 0xFF indicates that there are 255 or more
bytes available.
Check the I2C_RXF# line, which indicates whether the Receive buffer is full. This line indicates
that there is at least one empty byte available in the buffer. However, there is no indication of
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C master.
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C (Master receiver, Slave transmitter) and check whether the FT-X
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C toward the host computer), it is important to check if there is
FT201X USB I2C SLAVE IC Datasheet
Document No.: FT_000627 Clearance No.: FTDI# 264
2
C and if the data read
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