q3k / chubby75

Linsn RV901T HUB75 LED "Receiver Card" Reverse Engineering
Creative Commons Zero v1.0 Universal
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Replacing 74HC234 with input SN74CBT3245A #110

Open stanleyseow opened 1 year ago

stanleyseow commented 1 year ago

Not an issue but documentthe replacement of 74HC245 with SN74CBT3245A for INPUT pins

Reference Links :

Tweet URL : https://twitter.com/claude1079/status/1231194849350647808

Input Test : https://github.com/kittennbfive/5A-75B-tools/tree/master/I_want_inputs

Desoldering https://zeromips.org/posts/2022-05-29-5a-75b/

*** Be sure you add a diode to drop the 5V input voltage to drop the voltag to 4.3V

Part Number : SN74CBT3245APW

You should swap out U28 , that will give you INPUT pins for J1 ( R0, G0, B0, R1, G1, B1 ) and J2 ( R0, G0 )

8 pins should be a good start.

You can test the input pins iusing the above links ( https://github.com/kittennbfive/5A-75B-tools/) or create a flow in Ice Studio ( https://github.com/FPGAwars/icestudio/wiki )