Peb siv cov khoom siv hluav taws xob zoo sib xws rau peb hom: Source – charger; dab dej - mobile xov tooj; DRP - lub laptop lossis lub txhab nyiaj fais fab.
Rau peb hom khoom siv, yuav muaj 9 qhov sib xyaw ua ke ntawm kev sib txuas hauv kev xav. Yuav tsum muaj txoj kev sib txuas tsis ncaj ncees lawm (xws li adapter txuas adapter) lossis txoj kev sib txuas uas tsis paub tseeb tias leej twg yog Qhov Chaw (xws li lub txhab nyiaj fais fab lossis lub laptop). Yog li rau ntau qhov sib xyaw ua ke, Hom-C maub los teeb tsa lub interface li cas?
Hom-C maub los ua kom tiav tag nrho cov txheej txheem kev txheeb xyuas thiab kev sib txuas lus los ntawm lub xeev hloov ntawm lub xeev lub tshuab. Cov hauv qab no yog ob peb lub xeev tseem ceeb hauv lub xeev tshuab.
1. Unattached.SRC, Qhov chaw nyob hauv lub xeev tsis txuas
2. Unattended.SNK, Sink yog nyob rau hauv ib tug unconnected lub xeev
3. AttachWait.SRC, lub hom phiaj ntawm lub xeev no yog rau Qhov Chaw los xyuas kom meej tias CC1 thiab CC2 nyob ruaj khov tom qab lub cuab yeej txuas nrog
4. AttachWait.SNK, lub hom phiaj ntawm lub xeev no yog rau Sink kom ntseeg tau tias CC1 thiab CC2 nyob ruaj khov tom qab lub cuab yeej txuas nrog
5. Attached.SRC, Qhov chaw txiav txim siab tias cov cuab yeej txuas tau zoo
6. Attached.SNK, Sink txiav txim siab tias lub cuab yeej txuas tau zoo
5. Try.SRC, lub xeev no yog rau DRP ntaus ntawv sim hloov lub luag hauj lwm Source
6. Try.SNK, lub xeev no yog rau DRP ntaus ntawv sim hloov lub luag hauj lwm Sink
Scenario 1 Cwj pwm mechanism ntawm Qhov Chaw thiab Sink (adapter thiab xov tooj ntawm tes)
Cov hauv qab no yog tus cwj pwm kev coj cwj pwm thaum Source muaj Sink device txuas:
(1) Qhov chaw thiab dab dej yog ob qho tib si nyob rau hauv lub xeev unattached.SRC thiab Unattached.SNK
(2) Source detects that there is a pull-up resistor on the CC end of the Sink, and the Source state changes to Unattached.SRC --> AttachWait.SRC-->Txuas.SRC; Qhov chaw tig rau VBUS thiab VCONN.
(3) Sink detects VBUS, and the Sink state changes to Unattached.SNK --> AttachWait.SNK -->Txuas.SNK
(4) Tom qab qhov chaw thiab lub dab dej yog nyob rau hauv lub xeev txuas
Qhov chaw kho tus nqi Rp kom txwv qhov tam sim no absorbed los ntawm Sink
Sink pom qhov voltage vRd ntawm Rd los txiav txim qhov tam sim no tso cai los ntawm VBUS
Qhov chaw txiav txim siab seb lub dab dej puas raug cuam tshuam los ntawm kev saib xyuas CC. Yog tias nws raug rho tawm, nws nkag mus rau Unattached.SRC
Sink txiav txim siab seb qhov Source puas raug txiav los ntawm kev saib xyuas VBUS voltage. Yog tias nws raug rho tawm, nws nkag mus rau Unattached.SNK
Scenario 2 Cwj Pwm mechanism ntawm Qhov Chaw thiab DRP (charger thiab laptop)
Cov hauv qab no yog tus cwj pwm kev coj cwj pwm thaum qhov chaw muaj DRP ntaus ntawv txuas nrog:
(1) Ob Qhov Chaw thiab DRP yog nyob rau hauv lub xeev unattached
Qhov chaw nyob hauv Unattached.SRC xeev - DRP hloov ntawm Unattached.SRC thiab Unattached.SNK
(2) Source detects that there is a Sink pull-up resistor on the CC end, then the Source state changes to Unattached.SRC --> AttachWait.SRC -->Txuas.SRC; Qhov chaw tig rau VBUS thiab VCONN.
(3) When DRP switches to Unattached.SNK and detects that the CC pin is pulled up, the DRP state changes to Unattached.SNK --> AttachWait.SNK -->Txuas.SNK
(4) Tom qab Source thiab DRP nyob rau hauv lub xeev txuas
Qhov chaw kho tus nqi Rp kom txwv qhov tam sim no absorbed los ntawm DRP (ie Sink)
DRP (ie Sink) kuaj xyuas qhov voltage vRd ntawm Rd los txiav txim qhov tam sim no tso cai los ntawm VBUS
Qhov chaw txiav txim siab seb Sink puas raug txiav los ntawm kev saib xyuas CC. Yog tias nws raug txiav tawm, nws nkag mus rau Unattached.SRC- DRP (piv txwv li Sink) txiav txim siab seb qhov chaw puas raug cuam tshuam los ntawm kev saib xyuas VBUS voltage. Yog tias nws raug rho tawm, nws nkag mus rau Unattached.SNK thiab rov kho nws txoj kev hloov pauv ntawm Unattached.SRC thiab Unattached.SNK
Scenario 3 Cwj Pwm Mechanism ntawm DRP thiab Sink (Laptop thiab Txawb Xov Tooj)
Cov hauv qab no yog tus cwj pwm tus cwj pwm thaum DRP muaj lub dab dej txuas nrog:
(1) Ob leeg DRP thiab Sink yog nyob rau hauv lub xeev unattached
DRP hloov ntawm Unattached.SRC thiab Unattached.SNK - Sink nyob rau hauv Unattached.SNK xeev
(2) When DRP switches to Unattached.SRC and detects that the CC pin has a pull-down resistor, the DRP state changes to Unattached.SRC --> AttachWait.SRC -->Txuas.SRC; DRP (ie Source) tig rau VBUS thiab VCONN.
(3) When the Sink detects VBUS, the Sink state changes to Unattached.SNK --> AttachWait.SNK -->Txuas.SNK
(4) Tom qab Qhov Chaw thiab DRP nyob rau hauv lub xeev txuas
DPR (piv txwv li Source) kho tus nqi Rp kom txwv qhov tam sim no nqus los ntawm Sink - Lub Sink pom qhov voltage vRd ntawm Rd los txiav txim qhov tam sim no tso cai los ntawm VBUS
DRP (piv txwv li Qhov Chaw) txiav txim siab seb lub dab dej puas raug cuam tshuam los ntawm kev saib xyuas CC. Yog tias nws raug rho tawm, nws nkag mus rau Unattached.SRC thiab rov kho nws txoj kev hloov pauv ntawm Unattached.SRC thiab Unattached.SNK
DRP (piv txwv li Sink) txiav txim siab seb qhov chaw puas raug txiav los ntawm kev saib xyuas VBUS voltage. Yog tias nws raug rho tawm, nws nkag mus rau Unattached.SNK
Scenario 4 Behavior Mechanism ntawm DRP thiab DRP (Power Bank thiab Laptop)
Rau kev sib txuas lus ntawm DRP thiab DRP, muaj peb qhov xwm txheej. Hauv ib qho xwm txheej, ob lub cuab yeej txiav txim siab leej twg yog Qhov Chaw lossis Sink randomly; Hauv qhov xwm txheej thib ob, ib qho ntawm DRPs sim txiav txim siab los ua qhov chaw los ntawm Try.SRC mechanism; nyob rau hauv peb qhov xwm txheej, ib qho ntawm DRPs sim txiav txim siab ua Sink los ntawm Try.SNK mechanism.
Cov hauv qab no yog tus cwj pwm tus cwj pwm thaum lub cuab yeej DRP txuas nrog DRP:
Scenario 1:
(1) Ob qho khoom siv DRP yog nyob rau hauv lub xeev tsis txuas
DRP # 1 thiab DRP # 2 randomly hloov ntawm Unattached.SRC thiab Unattached.SNK
(2) When DRP#1 switches to Unattached.SRC and detects that the CC pin is pulled down by DRP#2, the state of DRP#1 changes to Unattached.SRC--> AttachWait.SRC -->Txuas.SRC; DRP # 1 (ie Source) tig rau VBUS thiab VCONN.
(3) When DRP#2 switches to Unattached.SRC and detects that the CC pin is pulled up, the state of DRP#2 changes to Unattached.SNK --> AttachWait.SNK -->Txuas.SNK
(4) Tom qab Source thiab DRP nyob rau hauv lub xeev txuas
DPR#1 (ie Source) kho tus nqi Rp kom txwv qhov tam sim no absorbed los ntawm DRP#2 (ie dab dej)
DRP # 2 (ie Sink) kuaj pom qhov voltage vRd ntawm Rd los txiav txim qhov tam sim no tso cai los ntawm VBUS
DRP#1 (piv txwv li Source) txiav txim seb Sink puas raug txiav los ntawm kev saib xyuas CC. Yog tias muaj, nws nkag mus rau Unattached.SRC thiab rov kho nws txoj kev hloov pauv ntawm Unattached.SRC thiab Unattached.SNK
DRP # 2 (ie Sink) txiav txim siab seb qhov chaw puas raug txiav los ntawm kev saib xyuas VBUS voltage. Yog tias muaj, nws nkag mus rau Unattached.SNK thiab rov kho nws txoj kev hloov pauv ntawm Unattached.SRC thiab Unattached.SNK
Case 2:
(1) Ob qho khoom siv DRP yog nyob rau hauv lub xeev unattached
DRP # 1 thiab DRP # 2 randomly hloov ntawm Unattached.SRC thiab Unattached.SNK
(2) When DRP#1 switches to Unattached.SRC and detects that the CC pin is pulled down by DRP#2, the state of DRP#1 changes to Unattached.SRC--> AttachWait.SRC -->Txuas.SRC; ; DRP # 1 (ie Source) tig rau VBUS thiab VCONN.
(3) When DRP#2 switches to Unattached.SRC and detects that the CC pin is pulled up, the state of DRP#2 changes to Unattached.SNK -->AttachWait.SNK
(4) DRP#2 is in AttachWait.SNK and wants to switch to the Source role. The state of DRP#2 changes to AttachWait.SNK -->Sim.SRC; thiab rub tus CC tus pin
(5) DRP#1 no longer detects DRP#2 pulling down the CC pin, so the state changes to Attached.SRC --> UnattachWait.SNK -->AttachWait.SNK; thiab tua VBUS thiab VCONN, thiab hloov lub rub-down resistor ntawm CC tus pin
(6) DRP#2 detects that the CC pin is pulled up, so its state changes to Try.SRC -->Txuas.SRC; thiab tig rau VBUS thiab VCONN
(7) The state of DRP#1 changes to AttachWait.SNK -->Txuas.SNK
(8) Tom qab Source thiab DRP nyob rau hauv lub xeev txuas
DPR # 2 (ie Source) kho tus nqi Rp kom txwv qhov tam sim no absorbed los ntawm DRP # 1 (ie Sink)
DRP # 1 (ie Sink) kuaj pom qhov voltage vRd ntawm Rd los txiav txim qhov tam sim no tso cai los ntawm VBUS
DRP#2 (ie Source) txiav txim siab seb Sink puas raug txiav los ntawm kev saib xyuas CC. Yog tias muaj, nws nkag mus rau Unattached.SRC thiab rov kho nws txoj kev hloov pauv ntawm Unattached.SRC thiab Unattached.SNK
DRP # 1 (ie Sink) txiav txim siab seb qhov chaw puas raug txiav los ntawm kev saib xyuas VBUS voltage. Yog tias muaj, nws nkag mus rau Unattached.SNK thiab rov kho nws txoj kev hloov pauv ntawm Unattached.SRC thiab Unattached.SNK
Qhov thib peb yog qhov Try.SNK mechanism, uas zoo ib yam li Try.SRC mechanism thiab yuav tsis tau piav qhia ntawm no.
Scenario 5 Tus Cwj Pwm Cwj Pwm ntawm Qhov Chaw thiab Qhov Chaw thiab nruab nrab ntawm Sink thiab Sink
Hauv ob qhov kev siv no, ob qho tib si Source thiab Sink yog nyob rau hauv Unattached.SRC thiab Unattached.SNK xeev, yog li tsis muaj hluav taws xob ntawm cov khoom siv.
Txog tam sim no, peb tau qhia qee qhov kev sib txuas lus sib txuas ntawm cov khoom siv. Tshwj xeeb tshaj yog rau ob lub DRP dual-lub luag hauj lwm pab kiag li lawm, hom-C maub los yuav siv Try.SRC los yog Try.SNK sim los tsim kom muaj lub zog mov logic. Yog lawm, yog tias qhov tsis ncaj ncees lawm lub hwj chim mov logic tshwm sim (piv txwv li, lub laptop them lub hwj chim bank), USB
PD raws tu qauv kuj tseem muab lub Hwj Chim Hwj Hwj Hwj Hwj Hwj Hwj Hwj Hwj Hwj Hwj Hwj Hwj Hwj Hwj Hwj Hwj Hwj Hwj kuj muab lub hwj chim Role Swap mechanism, uas hloov lub hwj chim mov lub luag hauj lwm los ntawm PD raws tu qauv. Yog xav paub ntxiv, thov mus saib ntawm USB Power Delivery Specification.