The MachXO2 family of programmable logic devices is optimized for low density applications, with an unprecedented mix of low cost, low power and high system integration. Now, with 10 new reference and demo designs, you can complete your design faster than ever.

Microprocessors often have a limited number of general purpose I/O (GPIO) ports that reduce pin count and shrink package size, but limit the number of I/Os to which a microprocessor can be connected. To allow more I/Os to be connected to microprocessors, I/O expanders or port expanders are used to provide I/O expansion capability. Most generic GPIO expanders use low pin count protocols, such as I²C or SPI, as the interface to the master. They allow designers to save the GPIO ports on the microprocessor for other critical tasks.

I²C Slave Peripheral Using Embedded Function Block
(Lattice Reference Design RD1124):

• Provides a programmable solution for serial expansion of GPIOs
• Uses an Inter IC Communication (I²C) interface between the microprocessor and the GPIOs
• Provides additional control and monitoring capabilities for a microprocessor when it does not have sufficient GPIOs to do the job
• Provides an I²C memory interface to the microprocessor

SPI Slave Peripheral Using Embedded Function Block
(Lattice Reference Design RD1125):

• Provides a programmable solution for serial expansion of GPIOs
• Uses a Serial Peripheral Interface (SPI) bus between the microprocessor and the GPIOs
• Provides additional control and monitoring capabilities for the microprocessor when it does not have sufficient GPIOs to do the job.
• Provides a SPI memory interface to the microprocessor

RAM-Type Interface for Embedded User Flash Memory
(Lattice Reference Design RD1126):

• Utilizes the User Flash Memory (UFM) block (available on MachXO2™-640/U and higher density devices)
• UFM block connects to the device core through the Embedded Function Block (EFB) WISHBONE interface. If desired, users can also access the UFM block independently through the hardened JTAG, I²C and SPI interfaces of the device.
• Facilitates user access to the MachXO2 EFB UFM module without the knowledge of WISHBONE protocol.