5 Configuration Mode Introduction
5.2 JTAG Configuration
UG290-2.3E
21(87)
5.2.2
Connection Diagram for the JTAG Configuration Mode
The connection diagram in the JTAG configuration mode is shown in
Figure 5-4 Connection Diagram for JTAG Configuration Mode
FPGA
JTAGSEL_N
TDI
TCK
TMS
TDO
JTAG PORT
4
.7
K
Note!
If JTAGSEL_N is not bonded out, when debugging the JTAG pin reuse, it is
suggested to set the MODE value to non-auto configuration mode (AUTOBOOT,
DUALBOOT or MSPI) before powering up the device to avoid the other bitstream
data affecting configuration. After power up and JTAG is configured manually, the
device enters User MODE, and JTAG pin will be used as a GPIO.
The clock frequency for JTAG configuration mode is no higher than 40MHz.
In addition to using JTAG to configure SRAM, the built-in Flash of
Gowin non-volatile FPGA devices (LittleBee
®
Family) and the external SPI
Flash of all other FPGA series programming can also be configured
through the JTAG pin. The connection for programming the built-in Flash of
the non-volatile devices is the same as that of the JTAG mode. Please refer
to Figure 5-41 and 8 Boundary Scan for external SPI Flash programming.
In addition, Gowin FPGA products support JTAG daisy chain operation,
which connects the FPGA TDO pin to the next FPGA TDI pin. Gowin
programming software will identify the connected FPGA devices
automatically and configure them in turn. The connection diagram for the
daisy chain configuration is shown in Figure 5-5.