5 Configuration Mode Introduction
5.8 SERIAL Mode
UG290-2.3E
65(87)
The connection diagram for the CPU mode is shown in Figure 5-48.
Figure 5-48 Connection Diagram for CPU Mode
8
FPGA
SCLK
D[7:0]
WE_N
CLK_HOLDN
Host
CLK
DATA
WE_N
CTRL
Note!
The figure above shows the minimum system diagram of the CPU MODE. The MODE
value is set to "111". The connections for the other fixed pins are shown in Figure 5-1.
Other than the power requirements, the following conditions need to
be met to use the CPU configuration mode:
CPU port enable
RECONFIG_N is not set as a GPIO during the first configuration after
power up or the previous programming.
Initiate new configuration
Power-on again or trigger RECONFIG_N at one low pulse.
5.7.1
Configuration Timing
Before configuration, make sure that MODE[2: 0]=111, and DONE will
be pulled up after configuration. If DONE or READY is pulled down, the
configuration fails.
In the configuration process, data bus D[7:0] is the MSB mode, and
the FPGA reads the data at the SCLK rising edge.
Figure5-49 CPU Mode Configuration Timing
5.8
SERIAL Mode
In SERIAL mode, Host configures Gowin FPGA products via serial
interface. SERIAL is one of the configuration modes that use the least
number of pins. The SERIAL mode can only write bitstream data to FPGA
and cannot readback data from FPGA devices; as such, the SERIAL mode
cannot read information on the ID CODE and USER CODE and status