In this Design Idea, an old technique of diode-based 16-to-4 encoding is combined with a new design, to scan a record number of buttons – 74 – with only four I/O pins! First start with the ancient ...

作为一个每天都会看 B 站的重度用户，我很喜欢 iPad 的屏幕比例，虽然看视频时有很宽的黑边，但这个黑边刚好可以容纳网友发的弹幕。 当然也有例外，在看一些比较老的剧集时，4:3 的画面比例让 iPad 的这一「优势」荡然无存的同时，也引起了我的好奇心：从 4 ...

As portable handheld communication devices proliferate, vendors are adding more features, such as digital video and audio, to meet consumer demand. The ISO MPEG-4 standard is emerging as the ...