Can STM32F101 run at 1 MHz?

[o239955]

Posted on July 22, 2009 at 12:04

Can STM32F101 run at 1 MHz?

[o239955]

Posted on May 17, 2011 at 13:18

Hi everybody,

I want to run my processor(STM32F101T4U6) at 1 MHz with HSI clock. But when i increase the AHB prescaler higher than 2, the processor doesn't working anymore. It is entering a dead lock.

Is it about the FLASH_ACR (latency,half cycle,prefetch)? What must be its value or how can i solve this problem?

[ This message was edited by: o.korkusuz on 21-07-2009 13:13 ]

[paulsmitton9]

Posted on May 17, 2011 at 13:18

According to the datasheet (table 16) the typical current should be 1.5ma (running at 1mhz) plus and extra 0.1ma for the internal oscillator.

I'd try and find out where your current is going (probably out of a port)

and reduce it if possible. Otherwise try leaving your peripherals running and putting the processor into sleep mode until an interrupt wakes it, or put it into stop mode if you can turn the peripherals off for a bit. This will reduce the average consumption.

[o239955]

Posted on May 17, 2011 at 13:18

OK the problem is solved. It was about the JTAG speed.

But still the power consumption is high. How can i decrease it? ADC must be on, USART must be on and 3-4 GPIO's are in use. Processor should consume maximum 2.5mA. What do you suggest?

[andreas2]

Posted on May 17, 2011 at 13:18

You mention JTAG speed... Maybe you have a dongle that is powered from the target? Also, the debugger may keep some clocks running even if you're using low power modes. Measure current with the debugger disconnected and the target running by itself.

And as always, make sure you don't leave unconnected pins floating.