I'm trying to use the 28335 experimenters kit with 16 inputs on GPIO32-47. I believe I have the registers initialized correctly (see register dump below) and GPIO 34-37 work as expected. However, GPIO32 and 33 appear to be stuck low. I measure just under 1V for these two pins. I noticed this problem on my experimenters kit where these pins are connected to an opto isolator. I also see the same problem on an unmodified experimenter's board (with the same control card) and it shows the same low voltage on these two pins.
I don't see anything on the schematic for the control card or experimenters kit that is pulling these two pins low?
Here is a dump of the relevant registers.
GPBCTRL 0x00000000 GPIO B Control Register (GPIO32 to 63) [Memory Mapped]
GPBQSEL1 0x00000000 GPIO B Qualifier Select 1 Register (GPIO32 to 47) [Memory Mapped]
GPBMUX1 0x00000000 GPIO B MUX 1 Register (GPIO32 to 47) [Memory Mapped]
GPBDIR 0x04000000 GPIO B Direction Register (GPIO32 to 63) [Memory Mapped]
GPBPUD 0x00000000 GPIO B Pull Up Disable Register (GPIO32 to 63) [Memory Mapped]
GPBDAT 0xFBFFFFFC GPIO B Data Register (GPIO32 to 63) [Memory Mapped]