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STM32F405 with LSI LS7266r1 / "8 bit bidirectional parallel bus" on STM32f4

Question asked by dengle.aaditya on Dec 19, 2014
Latest reply on Jan 25, 2015 by dengle.aaditya
     Its very new for me to work with any 32 bit MCU like STM32F405, I am having a handful experiance with AVR but not with ARM. 
     Here goes the situation where I have stucked.....
I have to compute linear encoder count and use it in CNC project. so far I could able to find that asking MCU to count the encoder is sheer waste of MCU resources and it makes all rest of the code dicy. There are lot of chances where we can miss the pulses. In any CNC (let it by any one for any purpose) loosing pulses are just not accepted, accuracy is everything. So to deal with the situation I decided to go with specialised hardware (Quadrature Counter IC / Quadrature Decoder) made by LSI CSI, LS7266r1. This was decided while I was working with  Atmega2560, now as the project is getting more and more complicated I have diverted the project to ARM STM32F405. the MCU is very ok for me (atleast for now) and its all other stuffs are going well except I cant able to drive LS7266r1 properly. 
     As per datasheet LS7266 has 8 bit Tristate parallel bus to do data transaction with MCU. being a data bus it is bidirectional in nature. To communicate with the IC I need to have a "8 bit bidirectional parallel bus" on GPIOC (other have been used for different purposes and only one have been left) I am using Bhasha Technology make TIGER Cortex M4 board, which has very limited documentation.
     Till now I have able to assemble a library (which is not with me right now but can post here by tomorrow) containing all necessary functionality for LS7266r1.
     Please help me to sort out "8 bit bidirectional parallel bus" over STM32F405. I cant find any way to put GPIO in bidirectional mode. Is it possible to do so? If so please guide me. If not please let me know the alternatives.
Thanks in advance.