The FT245BL is a USB-to-parallel FIFO interface chip manufactured by FTDI (Future Technology Devices International). The FT245BL is designed for use in applications where data needs to be transferred between a USB port and a parallel interface, making it particularly useful for bridging USB and parallel bus systems.
Package Type and Pin Function Specification
The FT245BL is typically packaged in a 32-pin LQFP (Low-profile Quad Flat Package), though this can vary in different versions. It has 32 pins, with each pin serving a specific function. Below is a detailed description of all 32 pins and their functions.
FT245BL Pinout and Function Table
Pin Number Pin Name Function Description 1 VCC Power supply pin (3.3V or 5V depending on the configuration) 2 GND Ground pin 3 TXD USB transmit data (Data out from the device to the host) 4 RXD USB receive data (Data in from the host to the device) 5 RST Reset signal input (Active low reset for the chip) 6 DTR Data Terminal Ready (Signal indicating data ready for transmission) 7 DSR Data Set Ready (Signal indicating that data is being received) 8 RTS Request to Send (Indicates the device is ready to receive data) 9 CTS Clear to Send (Indicates the host can send data to the device) 10 TXE Transmit FIFO Empty (Signal when the transmit FIFO is empty) 11 RXF Receive FIFO Full (Signal when the receive FIFO is full) 12 RD Read strobe (Read enable for the data bus) 13 WR Write strobe (Write enable for the data bus) 14 ALE Address latch enable (Signal to latch address information for the device) 15 IO1 Bidirectional data bus (part of the parallel interface) 16 IO2 Bidirectional data bus (part of the parallel interface) 17 IO3 Bidirectional data bus (part of the parallel interface) 18 IO4 Bidirectional data bus (part of the parallel interface) 19 IO5 Bidirectional data bus (part of the parallel interface) 20 IO6 Bidirectional data bus (part of the parallel interface) 21 IO7 Bidirectional data bus (part of the parallel interface) 22 IO8 Bidirectional data bus (part of the parallel interface) 23 IO9 Bidirectional data bus (part of the parallel interface) 24 IO10 Bidirectional data bus (part of the parallel interface) 25 IO11 Bidirectional data bus (part of the parallel interface) 26 IO12 Bidirectional data bus (part of the parallel interface) 27 IO13 Bidirectional data bus (part of the parallel interface) 28 IO14 Bidirectional data bus (part of the parallel interface) 29 IO15 Bidirectional data bus (part of the parallel interface) 30 IO16 Bidirectional data bus (part of the parallel interface) 31 IO17 Bidirectional data bus (part of the parallel interface) 32 IO18 Bidirectional data bus (part of the parallel interface)20 FAQ for FT245BL USB to Parallel FIFO Interface
Q: What is the FT245BL used for? A: The FT245BL is used for converting USB to a parallel FIFO interface, allowing devices with parallel data buses to communicate with USB-based systems.
Q: How does the FT245BL communicate with USB devices? A: The FT245BL uses the USB interface for data transmission, with data received via RXD and transmitted via TXD.
Q: What is the power supply requirement for the FT245BL? A: The FT245BL requires a 3.3V or 5V power supply, depending on the configuration.
Q: What is the function of the RST pin? A: The RST pin is used for resetting the chip, and it is active low, meaning the chip is reset when the pin is pulled low.
Q: How do I initiate a data transfer with the FT245BL? A: Data transfer is initiated through the use of the TXD (transmit) and RXD (receive) pins, with data sent between the USB host and the parallel interface.
Q: What is the role of the DTR and DSR pins? A: DTR (Data Terminal Ready) and DSR (Data Set Ready) are control signals used for signaling the availability of data for transmission or reception.
Q: Can the FT245BL be used in high-speed USB applications? A: Yes, the FT245BL supports USB high-speed data transfer modes.
Q: What does the IOx (IO1 to IO18) pins do? A: The IO pins (IO1 to IO18) form the parallel interface, and they are used for bidirectional data communication between the FT245BL and external devices.
Q: What is the significance of the TXE and RXF pins? A: TXE indicates when the transmit FIFO is empty, and RXF indicates when the receive FIFO is full, helping manage the flow of data.
Q: What is the function of the ALE pin? A: The ALE (Address Latch Enable) pin is used to latch the address information during parallel data communication.
Q: What is the maximum transfer speed supported by the FT245BL? A: The FT245BL supports USB full-speed (12 Mbps) and high-speed (480 Mbps) data transfer.
Q: Can the FT245BL be used in 5V systems? A: Yes, it supports both 3.3V and 5V systems, depending on the specific application.
Q: How is the FT245BL reset? A: The chip can be reset by applying a low signal to the RST pin.
Q: What is the WR and RD pins’ role? A: WR and RD are strobe signals used for writing and reading data, respectively, in the parallel interface.
Q: Can the FT245BL be used in embedded systems? A: Yes, it is widely used in embedded systems that require USB to parallel data conversion.
Q: Does the FT245BL support interrupt functionality? A: Yes, it can signal interrupts based on the status of FIFO buffers, including when the buffers are full or empty.
Q: How do I manage the parallel data bus signals? A: You manage the parallel data bus signals using the IO1 to IO18 pins for data transfer between devices.
Q: Is the FT245BL suitable for real-time data applications? A: Yes, it is suitable for real-time data applications that require fast communication between USB and parallel devices.
Q: Can the FT245BL interface with microcontrollers? A: Yes, the FT245BL can interface with microcontrollers that have a USB host capability.
Q: How do I know if the FT245BL is correctly connected to the system? A: The status can be monitored through the control signals such as TXE, RXF, and other interface signals.
