Describes two used buttons and Digital Drive IC

1. HD7279A is the first product with a high ratio in Beijing. It feels good and does not need to be used.

Crystal Oscillator, with 51 driver is very simple, manufacturers provideProgramSome time ago, we need to port it to stm32.

The driver did not succeed. It could occasionally reach the key value, which was very unstable and delayed for a few days.

His solution may be that the stm32 speed is too fast, but hd7279 cannot respond.
MATERIALS:
Http://www.bitcode.com.cn/hd7279_downloads.html

2. zlg7290 weekly meritorious service product, IIC interface. The crystal oscillator is required for external use.

Using it to make a small thing, also 51 driver, digital tube plus buttons.
MATERIALS:
Http://www.zlgmcu.com/search/SearchEx.asp? Q = zlg7290