Data Transfer Extension; Figure 21-14 Bus State Extension; Figure 21-15 Sclk Extension For Data Wait - Motorola DragonBall MC9328MX1 Reference Manual

• Relation between BS change and data
— When BS changes to shift to the next state, and Bus State is not extended, new BS is output
synchronizing with the output timing of final data LSB on SDIO in the previous state.
• TPC, data and CRC are MSB first
21.8.5.2 Bus State Extension
When it is difficult to switch BS signal in the same timing as the final data, in TPC State and Data State, it
is possible to continue that Bus State without switching the BS signal even after the final data transfer.
However, in Data State, HIGH must be output on SDIO during the period when Bus State is continued
without switching after the transfer of the last bit. In TPC State, signals on SDIO in this period are not
prescribed.

21.8.5.3 Data Transfer Extension

When data transferred from the MSHC module cannot be output to catch the next fall of SCLK, or data
transferred from the Memory Stick to the MSHC module cannot be received from the rise of next SCLK
because the MSHC module buffer is full, the next data transfer can be delayed by keeping SCLK high.
MOTOROLA
BS
SDIO D0
SCLK
Figure 21-14. Bus State Extension
BS
SDIO D1
SCLK
Figure 21-15. SCLK Extension for Data Wait
Memory Stick Host Controller (MSHC) Module
D7
D0 D7
Programmer's Reference
D6
D6
21-31