pub type PPRE1_W<'a, const O: u8> = FieldWriter<'a, u32, CFGR_SPEC, u8, PPRE1_A, 3, O>;
Field PPRE1 writer - PB low-speed prescaler (APB1)
PPRE1
HCLK not divided
HCLK divided by 2
HCLK divided by 4
HCLK divided by 8
HCLK divided by 16