Datasheet

Pin description STM8L151x2, STM8L151x3
30/112 Doc ID 018780 Rev 4
Note: The slope control of all GPIO pins, except true open drain pins, can be programmed. By
default, the slope control is limited to 2 MHz.
4.1 System configuration options
As shown in Table 4: Low density STM8L15xxx pin description, some alternate functions
can be remapped on different I/O ports by programming one of the two remapping registers
described in the “ Routing interface (RI) and system configuration controller” section in the
STM8L15x and STM8L16x reference manual (RM0031).
13228203
PA 0
(8)
/[USART_CK]
(2)
/
SWIM/BEEP/IR_TIM
(9)
I/O X X X
HS
(9)
XXPort A0
[USART1 synchronous
clock]
(2)
/ SWIM input
and output /
Beep output / Infrared
Timer output
40----V
SSIO
I/O ground voltage
39----V
DDIO
I/O supply voltage
1. At power-up, the PA1/NRST pin is a reset input pin with pull-up. To be used as a general purpose pin (PA1), it can be
configured only as output open-drain or push-pull, not as a general purpose input. Refer to Section Configuring NRST/PA1
pin as general purpose output in the STM8L15xxx and STM8L16xxx reference manual (RM0031).
2. [ ] Alternate function remapping option (if the same alternate function is shown twice, it indicates an exclusive choice not a
duplication of the function).
3. A pull-up is applied to PB0 and PB4 during the reset phase. These two pins are input floating after reset release.
4. 20-pin and 28-pin packages only.
5. In the open-drain output column, ‘T’ defines a true open-drain I/O (P-buffer and protection diode to V
DD
are not
implemented).
6. 20-pin packages only.
7. 28-pin packages only
8. The PA0 pin is in input pull-up during the reset phase and after reset release.
9. High Sink LED driver capability available on PA0.
Table 4. Low density STM8L15xxx pin description (continued)
Pin number
Pin name
Type
I/O level
Input Output
Main function
(after reset)
Default alternate
function
LQFP48
UFQFPN32 UFQFPN28 UFQFPN20
TSSOP20
floating
wpu
Ext. interrupt
High sink/source
OD
PP