5 Configuration Mode Introduction
5.2 JTAG Configuration
UG290-2.3E
29(87)
During loading, FPGA performs CRC check on the written data to
ensure that the data is written correctly, and whether CRC reports an error
can be used as a check mechanism to configure SRAM.
Table 5-7 Count of Address and Length of One Address
Device
Length of One Address (bits/address)
Count of Address
GW1N-1/GW1N-1S/
GW1NZ-1
1216
274
GW1N-2/GW1N(R)-4B/
GW1NS(E/R)-2(C)
2296
494
GW1N(R)-6/GW1N(R)-9
2836
712
GW2A(R)-18
3376
1342
GW2A(R)-55(ES)
5536
2038
The reading process is described in detail below, as shown in Figure
5-14.
1. Send the "0x15" instruction of ConfigEnable;
2. Send the "0x12" instruction of Address Initialize;
3. Send the "0x 03" instruction of SRAM Read;
4. Move the state machine to Shift-DR (data register) and
send as many clocks as the value of the address length, see Table 5-7.
When the last clock is sent, pull up TMS at the same time. The state
machine jumps to Exit1-DR, and TDO reads data with corresponding
length. The state machine will return to Run-Test-Idle state finally.
5. Repeat the step 4, the address will be automatically accumulated when
the data of an address are read each time;
6. Send the "0x3A" instruction of ConfigDisabled;
7. Send the "
0x02” instruction of Noop to end the reading process.