MSP430G2210: Count External Pulse of GAS Meter (Read Switch)

Hi Experts,

Our customer wants to design one product which is Non-Rechargeable Battery Operated.
Please help suggest ultra low power controller that can full-fill below requirements:
1) It can count external pulses using Read Switch
2) UART / I2C Support
3) Ultra low power consumption

I saw MSP430G2210 but not sure if this will fit his application. The customer also needs milliseconds HAL_Gettick() in Low Power mode. to calculate the difference of time in milliseconds between two Pulses. They also need a minimum pin (like 8 to 14). I hope you can help us.Thank you.

Kind regards,

Gerald