7 years ago.

interfacing Avago encoder HCTL2022 to mbed lpc178.

hi, i am using PMDC motor and interfacing avago interface ICHCTL2022, can i connect directly this encoder pulse to mbed lpc1768(using QEI interface ) or decoder is required? or i have to use any QEI hardware to connect encoder pulse? ? ?

1 Answer

7 years ago.

Hello Karunakar, if you want to use a ICHCTL2022 to decode your encoder, you have to connect it via a 8 bit databus. On page 18 of the datasheet you see the code for a Atmel AVR. You will need a lot of mbed pins, because you also have to connect the control signals.

If you want to connect the encoder pulses direct to the mbed, it will save you pins. You can use two inputs with interrupt. See Cookbook -QEI. The hardware QEI interface of the LPC1768 use two pins which are connected to mbed led's. You have to make a hack - see http://mbed.org/users/hexley/notebook/qei_hw-interface-implementation-notes/

The hardware interface will handle faster pulses.

Regards, Peter

Accepted Answer