|
|
JESD84-A44' \5 x6 ?% a( w5 d/ u
DAT0-DAT7: These are bidirectional data channels. The DAT signals operate in push-pull mode. Only. ~# m" {' C6 c+ s1 v1 s: X. I, y
the card or the host is driving these signals at a time. By default, after power up or reset, only DAT0 is
8 p( @, w& o/ }8 A0 WJEDEC Standard No. 84-A44 Page 15 used for data transfer. A wider data bus can be configured for data transfer, using either DAT0-DAT3 or DAT0-DAT7, by the MultiMediaCard controller. The MultiMediaCard includes internal pull-ups for data lines DAT1-DAT7. Immediately after entering the 4-bit mode, the card disconnects the internal pull ups of lines DAT1, DAT2, and DAT3. Correspondingly, immediately after entering to the 8-bit mode the card disconnects the internal pull-ups of lines DAT1–DAT7./ {7 c' x2 v! u3 k: g
# I. C I* m' n) A1 T1 H |
|