topic Using Low-power mode of MC9S08GB in 8-bit Microcontrollers

Using Low-power mode of MC9S08GB

TY — Thu, 14 Jun 2007 14:53:18 GMT

Hello all,

I'm writing program on the chip of MC9S08GT16 to enter low power mode periodically. I want it to enter STOP2, so write code in the initilization:

SOPT = 0x73; /* Enable STOPE */

SPMSC2 = 0x03; /* Set PDC and PPDC to 1 */

IRQSC = 0x16; /* Enable IRQPE */

SPMSC1 &= 0xF7; /* Disable LVDSE */

Every time I am about to enter STOP2, I switch to use internal clock, and SRTISC is set to be 0x17, to set RTI in every 1 sec.

I would like to know if anything is wrong, because I didn't notice it quitting from STOP2.

I used SMAC4.2 and CodeWarrior 5.1. Please let me know if I'm doing anything wrongly. Thanks a lot!

Tommy

Re: Using Low-power mode of MC9S08GB

Michele — Thu, 14 Jun 2007 17:09:40 GMT

what does it mean " I didn't notice it quitting from STOP2 " ?

Re: Using Low-power mode of MC9S08GB

TY — Fri, 15 Jun 2007 09:13:27 GMT

Hello,

As I understand, there should be a power on reset after exiting from STOP2, which should perform initialization again. Actually, my code toggles LEDs after initialization and perform data transmission using ZigBee transceiver, then move into STOP2 again. There should be LEDs toogles and change in current consumption, but none of those happened and I wonder it should be still in STOP2.

Tommy.