Title: LH7A400-10 Compact Flash Potential Issue

Applicable product:
Logic lce-app-10, pn 80000116
LH7a400-10 card engine

Content:
The zoom sdk application board provides a compact flash slot. This slot has A0 wired to the cf interface. The a400 memory controller when configured to be 16 bits wide in this memory area changes the functionality of A0 such that it becomes another nWE (write enable) signal.

Compact flash cards in memory mapped mode assume A0 to be in a stable state at logic 0. (however, testing at logic has shown that most compact flash cards are not be affected by this.) the Crucial brand 128MB compact flash card (and possibly others) is particularly sensitive to A0 being manipulated as a nWE line and will not function as intended with this type of interface.

Workaround:
Lift CF socket pin 20, and tie cf socket pin 20 to GND. On the SDK Application Board this is j7.20, on the IDK application board this is j8.20

Andrew Wawra
Logic Product Development