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Harald Welte wrote in an e-mail to the neo1973-hardware mailing list:
[...] apart from two differences, [the S3C2442B] is software/register-wise exactly identical to the s3c2440. Hardware-wise it is packaged with 64MByte (x32) SDRAM and depending on the type, 128/256MByte NAND flash (2k page size). The differences are: 1) all pull-up resistors (GPBUP, ...) are now pull-down 2) the default initializers for the PLL have changed [...]
The data sheet for the S3C2440A seems to be available at [1]. Samsung's page with more superficial information on the S3C2440 is at [2].
One difference is that the CPU voltage limits are specified variably from 400MHz (1.5V) to 50MHz (1V) the current at these speeds is not mentioned. The FreeRunner includes a variant that can be clocked up to 500MHz, however a) current consumption is insane at this frequency and b) various other components can't cope with the peripheral clock at this speed. It is therefore safe to assume that the highest frequency for the Neo FreeRunner is 400MHz.
It should also be possible to use host mode with externally-provided power. This will allow the FreeRunner to be connected to a USB device and be powered and charging the battery if present at the same time.
In addition you need to make sure EN_USBHOST signal that enables the physical Host mode power generation and disables the USB -> PMU charging path is deasserted. This may be taken care of automatically shortly by detection of the 48K resistor on a USB insertion leading to forcing EN_USBHOST deasserted. The charge pump that generates the 5V in host mode doesn't seem to mind getting external 5V given to it, but the real issue is that the battery will not be charged at all if we leave EN_USBHOST asserted since one of its jobs is to stop that happening.