USB suspend mode

[georges_emmanuel]

Posted on August 16, 2006 at 14:58

USB suspend mode

[georges_emmanuel]

Posted on August 11, 2006 at 14:42

Hi all,

do you know if there's an issue, i just would like to respect USB standard during suspend mode and draw less than 500µA. So in ''usb_pwr.c'' (in Suspend() and Resume()) I can handle power management and clock source . I would like to stop external oscillator by gpio, go in low power mode (ie. LPWFI or STOP) without RTC 32kHz quartz on board (maybe I should add it), and I would like to be wakeup by USB (XTI line 1). I wonder what does it mean the Free Running Pll, but it seems to be my last chance (see attached picture). Although there is no FreeRunningClock in SlowClock_Typedef: void LPWFI(SlowClock_Typedef clock,FunctionalState VRstate) in advance thx. ________________ Attachments : an2100page10.jpg : https://st--c.eu10.content.force.com/sfc/dist/version/download/?oid=00Db0000000YtG6&ids=0680X000006HtTE&d=%2Fa%2F0X0000000aQQ%2F2XFBVMt_L4pykeUn2.awJElmLQFvgXPfhGeqDQ_qzVU&asPdf=false

[georges_emmanuel]

Posted on August 16, 2006 at 14:58

I found in last release of USB lib. some info, but not sure of it.

In USB_PWR.c during suspend a function call to Enter_LowPowerMode and during resume_init a function call to Leave_LowPowerMode. I've tried it but nothing happened, the micro don't got any clock. void Enter_LowPowerMode(void) { /* RCCU->CCR |= RCCU_CKAF_SEL_Mask; RCCU->CFR &=~0x1; //PLL not sys clock RCCU->PLL1CR &=~0x80; //Free running off GPIO_Config(GPIO0,0x4010,GPIO_OUT_PP); GPIO_Config(GPIO1,0x8400,GPIO_OUT_PP); GPIO_WordWrite(GPIO0,0x0); FLASHR->CR0|=0x8000; //disable the flash during the LPWFI PCU->PWRCR |=0x8000; //disable MVR during WFI mode PCU->PWRCR |=0x0010; RCCU->CCR |=0x2; //select the 32KHz as peripherl clock during LPWFI RCCU->CCR |=0x1; GPIO_Config (GPIO0, 0x1000,GPIO_HI_AIN_TRI); //Disable External oscillator P0.12 RCCU->SMR &=0xFE; // enter LPWFI*/ } void Leave_LowPowerMode(void) { /* GPIO_BitWrite(GPIO0,12,0); */ /*Enable External oscillator*/ /* GPIO_Config(GPIO0,0x1000,GPIO_OUT_PP); Set_System(); Set_USBClock();*/ }