A chip with probable silkscreen “HM82C42” was found. Googling does not turn up anything but given the amount of traces going to this chip, I’m going to suspect this is the keyboard controller to the PS/2 interface.
A PC's keyboard controller is also known as an 8042, based on the original Intel microcontroller it used, so 82C42 is obviously a variant of it from a different manufacturer. No surprise that Google doesn't work --- it's gotten increasingly horrible for finding less well-known part numbers and such: https://news.ycombinator.com/item?id=36195600
I suspect someone may have gotten a batch of NOS embedded PC boards with this SoC and decided it would be a good opportunity to sell them to the retrocomputing community. That explains the CF and choice of I/O, as well as the 94-95 datecodes on the ICs.
Indeed, the 82C42 is a keyboard controller. The original 8042 was a microcontroller that had the keyboard controller code burned into the onboard ROM. I am using an 8242 variant right now from VT for a multi-cpu 68k project. There are a few different variants, but the most common one has the standard PS2 keyboard+mouse support.
I think this is a custom board (especially given the lithium battery and USB charging), but they copied the design from an industrial using the M6117. I've seen a ton of devices that use the same pair of an M6117 and a CHIPS F65535 VGA chip. You can still find stocks of both on places like Utsource. I do wish they had just gone with the more modern Vortex86 instead, perhaps someone will design an open hardware equivalent to this device that uses one of them instead.
A PC's keyboard controller is also known as an 8042, based on the original Intel microcontroller it used, so 82C42 is obviously a variant of it from a different manufacturer. No surprise that Google doesn't work --- it's gotten increasingly horrible for finding less well-known part numbers and such: https://news.ycombinator.com/item?id=36195600
I suspect someone may have gotten a batch of NOS embedded PC boards with this SoC and decided it would be a good opportunity to sell them to the retrocomputing community. That explains the CF and choice of I/O, as well as the 94-95 datecodes on the ICs.