1 sdram, 2 sd card, 3 spi flash – Artesyn COMX-P1022 Installation and Use (July 2014) User Manual
Page 59: 1 sdram 4.3.2 sd card 4.3.3 spi flash, Figure 4-3, Spi area for u-boot

Functional Description
COMX-P1022 COM Express Module Installation and Use (6806800M04C)
59
4.3.1
SDRAM
COMX-P1022 COM Express Module only supports 2 GB DDR3 667 MT/s DDR3+ECC arranged in
two ranks in one slot.
4.3.2
SD Card
COMX-P1022 COM Express Module has a microSD card slot on-module with a 2 GB SD card
installed. The SD card stores the Bootloader and the Operating System.
The eSDHC acts as a bridge, passing host bus transactions to SD/MMC cards by sending
commands and performing data accesses to or from the cards. It handles the SD/MMC
protocol at the transmission level.
4.3.3
SPI Flash
COMX-P1022 COM Express Module has an SPI socket on-module with a 4 MB SPI Flash installed.
The U-Boot is installed in the SPI flash on module.
The flash was divided into 3 areas: configure data, U-boot, and Environment argument area.
Figure 4-3
SPI Area for U-boot