4700 FPGA Functionality

From Technologic Systems Manuals

All macrocontrollers feature an FPGA. Any external interfaces called for by the TS-SOCKET specification that are not provided by the CPU are implemented in the FPGA whenever possible. The FPGA is connected to the CPU by a static memory controller, and as a result the FPGA can provide registers in the CPU memory space.

While most common functionality is accessed through layers of software that are already written, some features may require talking directly to the FPGA. Access to the FPGA is done through either the 8-bit or 16-bit memory regions. Code should access 16-bit or 8-bit depending on the access designed for the specific hardware core. For example, the CAN core is 8 bit, the 8 bit MUXBUS space is 8 bit, and some 8 bit cycles are needed for the SPI core if you want to do 8 bit SPI transactions. To access hardware cores in the FPGA, add the offset in the table below to the base address.

Bit Width Base Address
16 0x80000000
8 0x81000000
Offset Usage Bit Width
0x0000 16KB blockram access (for XUART buffer) 16
0x4000 Syscon registers 16
0x4400 ADC registers (for off-board ADC) 16
0x4800 SPI interface 16
0x4C00 CAN controller 8
0x4D00 2nd CAN controller 8
0x5000 Touchscreen registers 16
0x5400 XUART IO registers 16
0x8000 32KB MUXBUS space 16/8