STM8S903K3 STM8S903F3
Option byte no.
Option bytes
Description
0: No reset generated on halt if WWDG active
1: Reset generated on halt if WWDG active
OPT4
EXTCLK: External clock selection
0: External crystal connected to OSCIN/OSCOUT
1: External clock signal on OSCIN
CKAWUSEL:Auto wake-up unit/clock
0: LSI clock source selected for AWU
1: HSE clock with prescaler selected as clock source for for AWU
PRSC[1:0] AWU clock prescaler
0x: 16 MHz to 128 kHz prescaler
10: 8 MHz to 128 kHz prescaler
11: 4 MHz to 128 kHz prescaler
OPT5
HSECNT[7:0]:HSE crystal oscillator stabilization time
0x00: 2048 HSE cycles
0xB4: 128 HSE cycles
0xD2: 8 HSE cycles
0xE1: 0.5 HSE cycles
8.1
STM8S903K3/F3 alternate function remapping bits
Table 13: STM8S903K3 alternate function remapping bits [7:2] for 32-pin packages
Option byte no.
Description(1)
OPT2
AFR7 Alternate function remapping option 7
0: AFR7 remapping option inactive: Default alternate functions(2)
.
1: Port C3 alternate function = TIM1_CH1N; port C4 alternate
function = TIM1_CH2N.
AFR6 Alternate function remapping option 6
0: AFR6 remapping option inactive: Default alternate function(2)
.
1: Port D7 alternate function = TIM1_CH4.
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