More chip selects

Do you have a question? Post it now! No Registration Necessary

Translate This Thread From English to

Threaded View
Hello all,

I have a CPU board which has a M16C/62P microcontroller and the
microcontrollers
three CS pins are connected to SRAM, EEPROM and ADC.
Now I need to add LCD to the CPU board throuch the latch and I will
need
one more CS pin to the latch.

I am thinking to expand one of the microcontrollers CS pin to get two
CS pins using address decoder in a way that this microcontrollers CS
pin comes to the
address decoder and based on address it selects one of the two CS
pins.

Is there other possibilities mayby to expand CS pins?

Re: More chip selects

Quoted text here. Click to load it

Doesn't sound like a homework problem to me, so I'll take a stab:

Address decoding, the method that you describe, is the most common.
And probably second most common would be indirect access, where you
control which block or device gets the CS by way of writing to a
control bit somewhere - for example: some sort of writable register on
your data bus (which would need its own address decoding unless you
have an unused data bit), or using a GPIO line, if one is available.

   Marc

GPIO = general purpose I/O


Site Timeline