just hook up the crystal to correct pins, that is all. we just connect them as per reference schematic.Ī13 need 24 Mhz crystal as clock source, the CPU has on chip PLL, everything else is taken care by the internal clock block. almost all the reference schematic have same IC.Īllwinner A13 is the CPU, it comes in eTQFP176 package, does not have many configuration gpio, only uboot pin ,reset line and few other stuff is there.
Power, all highspeed CPU need many power rails, our CPU needĪXP209 has two switching regulators, 1.6A and 1.2A capable and total 5 LDO, all outputs are configurable over I2C from the host.has ADC, soft start ,li-Ion battery charger and many other things. Internal 24-bit Audio Codec for 2-Ch headphone and 1-Ch microphoneġ. Internal 4-wire touch panel controller with pressure sensor and 2-point touch One UART with only TX/RX and one UART with RTS/CTS Three high-speed memory controllers supporting SD version 3.0 and eMMC version 4.3 One USB 2.0 OTG controller for general application and one USB EHCI/OHCI controller for host application
The processor is though Chinese but has some decent hardware, specification are given blow click here to goto my github repo to view all the document available with me. There is lots of data available through various source,available data is more then what we need. but i have found few offical looking schematic from the allwinner itself, you can download them here,as all olimex board are open source schematic and PCB design file are available to download from there github repo to get minimum system schematic the good point to start is the reference schematic provided by the manufacturer it self ,as we know allwinner does not have much direct support. It is descent size CPU, it has 16 bit DDR2/DDR3 interface ,there are going to many connections.
When you are making your own board the place to start is processor's datasheet, there you need to look at few key points, pinout, package, power rails, clock, configuration gpio(if there),external memory interfaces RAM and ROM.
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