Beaglebone black not booting if connected to buffer IC 74AVC16T245

Hello,
I am using beaglebone black with ubuntu(3.8.13-kernel). I want to interface 7" TFT-Lcd with baglebone black. I designed a hardware with tranceiver (buffer) IC74AVC16T245 which is connected to GPIO ports of beaglebone black. And 40 pin LCD connector is connected to output of tranceiver IC. OE pin is connected to ground. DIR pin is also connected to ground.
Now, I am facing a problem with hardware. If I connect this hardware with beaglebone black, beaglebone black is not booting only power led is on. When I remove that hardware, beaglebone black board is booting properly. I tested a hardware but I didn’t found any mistake. Can i get some guidance or idea to solve this problem?? Thanking you.

Regards,
Kishor.

Go read section 8.1.1 of the beagle bone black SRM about the LCD pins and check exactly what pins exactly do you have this buffer connected to? if the buffer connects to any pins P8.31-46 then P9.10 SYS_RESETn must be used to control nOE bar on the IC74AVC16T245. An inverter will likely be required to get the sense right. At present with nOE bar grounded the IC74AVC16T245 would be driving the boot pins.or at the very least placing a load upon them. I’m willing to bet that the board will boot just fine with the IC74AVC16T245 connected and nOE bar pulled up to vcc instead of being grounded.

Eric

Yes, please. If you plan to make HW for this board, reading the manual is always a good idea.

Gerald

Hello Eric and Gerald,