Getting a BS1 - need advice for connecting multiple devices
Archiver
Posts: 46,084
My local electronics store has the Basic Stamp 1 on special for a
bargain, so I figured I'd get it.
What I want to do is hook it up to a 16x2 LCD, 16 digit input, RS-232
for the computer (fine so far, already in an application note) and a
serial EEPROM - therein lies the problem.
I've worked out a couple of ways it might be possible:
1) By compressing the RS-232 onto a single i/o pin - is this possible,
given that I won't be reading and writing at the same time?
2) By setting up some sort of bus system to allow me to change the
chip-select - I was thinking a decade counter or similar.
This leads to a few questions:
Can anyone think of a design for this that doesn't use any sort of bus
system, simply with clock-selects etc?
If a bus system is needed, does anyone have some circuit diagrams for
examples?
When a chips chip-select is low, what does it do with the data lines?
Does it let them float? If so, I should be able to use a bus system that
simply changes the chip-select to give attention to each chip, otherwise
I'd need some way to only allow one chip to communicate with the stamp
altogether. Once again, does anyone have some diagrams? [noparse]:)[/noparse]
For reference, I used to do a bit of electronics as a hobby, but it's
been a while... :P
Nick
bargain, so I figured I'd get it.
What I want to do is hook it up to a 16x2 LCD, 16 digit input, RS-232
for the computer (fine so far, already in an application note) and a
serial EEPROM - therein lies the problem.
I've worked out a couple of ways it might be possible:
1) By compressing the RS-232 onto a single i/o pin - is this possible,
given that I won't be reading and writing at the same time?
2) By setting up some sort of bus system to allow me to change the
chip-select - I was thinking a decade counter or similar.
This leads to a few questions:
Can anyone think of a design for this that doesn't use any sort of bus
system, simply with clock-selects etc?
If a bus system is needed, does anyone have some circuit diagrams for
examples?
When a chips chip-select is low, what does it do with the data lines?
Does it let them float? If so, I should be able to use a bus system that
simply changes the chip-select to give attention to each chip, otherwise
I'd need some way to only allow one chip to communicate with the stamp
altogether. Once again, does anyone have some diagrams? [noparse]:)[/noparse]
For reference, I used to do a bit of electronics as a hobby, but it's
been a while... :P
Nick