Devices HT32F12xx Series HT32F12xx Series Holtek Devices 4 HT32F1251 HT32F1251B/51/52/53 Cortex-M3 HT32F1251B HT32F1251B/51/52/53 Cortex-M3 HT32F1252 HT32F1251B/51/52/53 Cortex-M3 HT32F1253 HT32F1251B/51/52/53 Cortex-M3