Arduino for STM32

Timers 6 and 7 have a current value register (see TMRx_CVAL). It looks like the maximum rate they can count is 120Mhz (figure 4-1 in the data sheet says 240Mhz but this looks like an error). You could count how many times they wrap around in a second to verify their count frequency after configuring...

You could make a rough estimate of the CPU clock speed by measuring the current consumption of the board with code running in a tight loop and no peripherals enabled. According to the Artery data sheet for the ATF403A series the chip current consumption varies from 3.58mA at 8MHz up to 41mA at 240Mh...