Cyclone IV FPGA Development Log

Last semester, the school offered a digital systems course, which involves development on FPGAs. At the end of the course, we need to gather in groups and achieve some complicated functionality with the flexible architecture of FPGA, such as creating a game or running a convoluted neural network. We are free to add extra functionalities as we wish. Our group has done a game similar to Raiden, or controlling a fighter jet and attacking enemies with bullets. In addition to course requirements, we implemented these extra functionalities: A 640x480 VGA framebuffer with 16-bit color depth, stored on SRAM chip Naturally, Simplified Chinese fonts are included (full UTF-8 Chinese range, but without punctuation marks, since they are out of that range and we're kinda lazy)...

Illustration for Writing Stories in Traceroute

Writing Stories in Traceroute

2020-10-11 Update Now a better way exists that doesn't involve a bunch of Docker containers. Please refer to Writing Stories in Traceroute, Elegantly . Intro Traceroute is one of the popular tools for network inspection. It shows the IP addresses of routers on the route from your computer to a destination server, similar to: Domains are shown on the last 2 hops, which is the IP's reverse DNS record. Reverse DNS records exist as PTR records in the format of 4.3.2.1.in-addr.arpa . For more information, you may refer to Setting IP Reverse Records in DN42 (Chinese Only) . However, PTR records need not be real domains. They can be any string that "looks like" a domain. With this, we can write one sentence on each hop of a Traceroute path to make a story: This story is set up in DN42....

RoboMaster Development Log (Updated 2018-05-28)

Our school organized a RoboMaster team and planned to attend the competition this year. Since we are all new students at a new campus, we do not have any reference materials available from previous students, and we have to figure out bugs after bugs on our own. This post describes some of the problems we met during software development. Hardware: RoboMaster Official Development Board MCU Model: STM32F427IIHx Software: ChibiOS 18.2.0 Board Has 12 MHz HSE Clock Instead of Commonly Seen 8MHz The pitfall is that neither the manual nor the hardware schematics mentioned the clock frequency. Due to this problem, the actual frequency we programmatically set with STM32CubeMX or other software is much higher than expected. This caused the following problems:...