Boot from SD-Card - Again

Hello,
I own a tbs2910 version 2.1 with the DIP-Switch to easily select where to boot from. According to a documentation cited in some threads on this board there are 2 possibilities:
Boot from MMC4 (SD2) and boot from MMC2 (SD3).
Can someone tell me what MMC4 and MMC2 refer to? There is the SD-Card and there is the Micro-SD-Card. So which is which????
Thank you
Michael
I own a tbs2910 version 2.1 with the DIP-Switch to easily select where to boot from. According to a documentation cited in some threads on this board there are 2 possibilities:
Boot from MMC4 (SD2) and boot from MMC2 (SD3).
Can someone tell me what MMC4 and MMC2 refer to? There is the SD-Card and there is the Micro-SD-Card. So which is which????
Thank you
Michael