Timer update generation delay Hello,I am verifying timer functionality on an STM32F303K8 Nucleo development board. After generating an update event, the counter register does not update immediately - in downcounting mode, it takes several nops for the counter to read the same as the auto-reload value. A code sample is attached below. Without the fifth nop, the counter reads 0 rather than 999. .syntax unified
.thumb
.global main
main:
/* APB1 enable TIM2 */
ldr r1, =0x40021000
ldr r0, [r1, #0x1C]
orr r0, r0, #1
str r0, [r1, #0x1C]
/* TIM2 set URS and DIR*/
ldr r1, =0x40000000
mov r0, #0x0014
str r0, [r1]
/* TIM2 frequency 1kHz */
mov r0, #7999
str r0, [r1, #0x28]
/* TIM2 reload 1s */
mov r0, #999
str r0, [r1, #0x2C]
/* TIM2 generate update event */
mov r0, #1
str r0, [r1, #0x14]
nop
nop
nop
nop
nop
/* TIM2 get count */
ldr r0, [r1, #0x24]
end:
bkpt
b end I tried alternatively to use a DSB after the update generation with no effect. This might be a contrived example, but for an API,
