AT43USB325 datasheet(93/109 Pages) ATMEL

93 / 109 page

3355C–USB–4/05

AT43USB325

8.5.4

Suspend and Resume Process

8.5.4.1

Global Suspend

The Host stops sending packets, the hardware detects this as global suspend signaling and

stops all downstream signaling. Finally, the hardware asserts the GLB_SUSP interrupt.

8.5.4.2

Global Resume

The Host resumes signaling, the hardware detects this as global resume and propagates this

signaling to all downstream ports. Finally, the hardware enables the oscillator and asserts the

RSM interrupt.

Hardware

Firmware

Host stops sending packets

Global suspend signaling

detected

Stop downstream signaling

Set GBL SUS bit

→ interrupt

Shut down any peripheral activity

Set Sleep Enable and Sleep Mode

bits of MCUCR

Set GPIO to low power state if

required

Set UOVCER bit 2

Execute SLEEP instruction

10. SLEEP bit detected

11. Shut off oscillator

Hardware

Firmware

Host resumes signaling

Resume signaling detected

Propagate signaling downstream

Enable oscillator

Set RSM bit

→ interrupt

Reset RSM and GBL SUSP bits

Restore GPIO states if required

Clear UOVCER bit 2

Enable peripheral activity

AT43USB325 Datasheet(PDF) 93 Page - ATMEL Corporation

AT43USB325 Datasheet(HTML) 93 Page - ATMEL Corporation

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL