|
2 _, l/ y$ s y# t$ k* s
挨打沒死六 官網討論版
; F8 J N3 a% d; M/ c3 w4 b
7 G8 s2 x$ L" U1 M& X問題:' \0 x& }2 N Y- d
Dear expert,
# S% A" b( h4 w5 E' m: C+ kIn i.MX6SL platform, we use eMMC for data storage. Do we need the pull-up resistors at the datas (data0 to 7) and CMD signal?1 L. E, e) X6 K8 @, W7 e& |) J5 m, Q
thanks,
: E3 w2 R- G4 `3 F+ s3 W$ ~ J) {+ y
( h( v4 J# p( N/ m回覆︰ ~" \6 `' a" O' a
There is no special requirement for external resistors pulling up regarding the i.MX6 SL eMMC interface. You may look at the i.MX6 SL EVK design schematic.; a/ ~5 h+ q' ]4 z& o4 F
! h* h4 h+ r$ x According to JEDEC specs : $ z, X# e% X" t7 w) _* I
“JEDEC eMMC includes internal pull-up resistors for data lines DAT[7:1]. Immediately after entering the 4-bit mode, the device disconnects the internal pull-up resistors on the DAT1 and DAT2 lines. (The DAT3 line internal pull-up is left connected.) Upon entering the 8-bit mode, the device disconnects the internal pull-ups on the DAT1, DAT2, and DAT[7:4] lines.”
" F3 q5 ~7 s1 V' n8 y
& Y' d# p) `, a8 i
9 H4 z' @% u; f; Z" q
9 d- b/ v# j. |9 C% [' f* N |
|