Convert CF633 from USB to serial


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What I have:
CF 633 H/W v1.3 F/W v1.5, with the USB daughter board.

What I'd like:
I'd like to use this in an embedded project, driving it with an AVR. There is no USB host controller, but I've got plenty of UARTs.

I've seen a bunch of posts about removing the daughter board, which I'm willing to do. It's not clear to me whether the existing firmware on the 633 will work over the pure serial interface, or whether the 633 would need a brain transplant.

If I'm reading the datasheet correctly, I'm going to want JP11 and JP12 to be closed, and JP18 to be open, since I'll be driving the serial connection with the AVR's logic levels (3v0-ish, I believe). Correct? I'm guessing they may already be set this way if my assumptions about what's on the daughter board are correct, but we'll see.

Finally, I see no RoHS silkscreens on either the main or daughter board. The main board says Copyright 2002. Is it safe to assume this board is pre-RoHS? (Just trying to avoid, um, issues from my friends in the lab about contaminating their tools).

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The module can be converted back by removal of the daughter board, and closing / opening of a number of jumpers. It would also be possible to configure the module for logic level serial as well as you are going to be working with an embedded system. The module works at a 0-5v logic level. If your host system is 0-3v, you will need a level inverter.

The firmware is the same for serial or USB. The interface is hardware driven.

After removal of the USB daughter board you will want to do the following:
* Verify JP11 and JP12 are closed
* Verify JP18 is open
(these jumpers are changed for the installation of the USB daughter board).
* Close jumpers JP2 and JP4. This will bring your Rx and Tx lines back to normal configuration as follows:
- LCD Tx / Host Rx - pin 2
- LCD Rx / Host Tx - pin 3

If the PCB is not silk-screened RoHS, and the copyright is 2002, I'm afraid the module is not RoHS compliant. The v1.3 PCB is a few revs back and is NOT RoHS compliant.