Configuration Interfaces - Configuration Interfaces - UG860

Spartan UltraScale+ FPGAs Configuration User Guide (UG860)

Document_ID
UG860
Release_Date
2026-07-27
Revision
v1.3 English

AMD Spartan™ UltraScale+™ FPGAs have five configuration interfaces. The configuration interface is selected with the configuration mode pins M[2:0].

The mode input pins M0, M1, and M2 pins must be set at a constant DC voltage level, either through a pull-up or pull-down resistor (<1 kΩ), or tied directly to ground or VCCO_0. For configuration initiated via assertion of the PROGRAM_B pin, the M[2:0] input values must be set before the deassertion of PROGRAM_B. The M[2:0] input value must be held at least throughout device configuration initialization, which is the period when the device is driving INIT_B Low.

For detailed configuration interface timing information, see the Spartan UltraScale+ FPGA Data Sheet: DC and AC Switching Characteristics (DS930). Each configuration interface corresponds to one or more configuration modes and bus widths, shown in the following table.

Table 1. Configuration Modes
Configuration Mode M[2:0] Bus Width Clock Direction
JTAG(1) 101 x1 Input (TCK)
Master SPI_24(2) 001 x1, x2, x4 Output (CCLK)
Master SPI_32(2) 010 x1, x2, x4 Output (CCLK)
Master OSPI 011 x1, x8 Output (CCLK)
Slave SelectMAP 110 x8, x16, x32 Input (CCLK)
Slave Serial 111 x1 Input (CCLK)
  1. It is recommended to implement a board-level switch or jumper that allows a board to switch from the target configuration mode to the JTAG configuration mode if JTAG is not the primary mode. Devices should be set to JTAG configuration mode during board-level JTAG boundary-scan testing and the mode can be used for loading prototype designs.
  2. Spartan UltraScale+ FPGAs support a master SPI 24-bit addressing configuration mode (SPI_24) or a SPI 32-bit addressing configuration mode (SPI_32). The SPI_32 configuration mode option sends 32-bit addressing commands that addresses flash sizes greater than 128 Mb. See Configuration and Mode Setting for more information.