FPGA, SoC, And CPLD Boards And Kits
FPGA Evaluation and Development Kits

Communicate sim900 with DE2

Honored Contributor II

Hi everybody, 


I am doing a projects that use GPS module sim900 to communicate with FPGA DE2. 

The module sim900 has 1 UART interface to command out, simply it has only 3 lines RXD and TXD and ground. 


I designed a system-on chip based ARM and some interfaces (of course it has UART as well), and then loading design into DE2 kit. 

I connected 3 lines of UART interface from sim900 with 3 GPIO pins (UART in my design used GPIO from board), but not sure why I cannot get any signal back after turning on the sim900 circuit. 


I also test separately sim900 + PC and my design + PC and they are working normaly. 


Anybody has experience on this case. Many thanks... 


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Honored Contributor II

Have you tested the RS232 independent of the GPS unit?

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