Adding a ram chip-Help!!!
Hi to all:
I've just ordered a board and the Bs2sx and am wondering
if I could add a 8k by 8 ram chip (I think something like the 27C64...)?
I'm planning on doing some wirewrapping with the experiments, and have a ram
chip
and eeprom I'd like to add.
Is it easy to multiplex the address and data to and from the chip?
Thanks,
Art
I've just ordered a board and the Bs2sx and am wondering
if I could add a 8k by 8 ram chip (I think something like the 27C64...)?
I'm planning on doing some wirewrapping with the experiments, and have a ram
chip
and eeprom I'd like to add.
Is it easy to multiplex the address and data to and from the chip?
Thanks,
Art
Comments
The Stamp doesn't have an external address and data bus. You'd have to
treat the device as an external I/O device and tie up lots of pins. They
do make serial EEPROMs that work well (although not very speedy). There
are a few serial RAM products out there as well.
If you wanted to use a 27C64 (a EEPROM) and you only wanted to access it
sequentially, you could connect a counter like a 4040 to two I/O pins
(clock and clear). This would generate your address (might need to
cascade to get the correct number of bits). Then you'd also need 8 bits
for data (tie OE permanently low). So then you could pulse the counter
to read the next address. I have a EPROM programmer that works like
that.
Good luck!
Al Williams
AWC
* Easy RS-232 Prototyping
http://www.al-williams.com/awce/rs1.htm
>
Original Message
> From: Art Burke [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=8BdC5LpVuhLhhA09Wd8jc6Gq-xSNV5MlrVJV1ojGTkqbSQKnjxM6PaVv79uuzf5yL7TCmu-sjbaqWwS5YfuajIjt]pianomanab@s...[/url
> Sent: Thursday, November 29, 2001 8:02 AM
> To: basicstamps@yahoogroups.com
> Subject: [noparse][[/noparse]basicstamps] Adding a ram chip-Help!!!
>
>
> Hi to all:
>
> I've just ordered a board and the Bs2sx and am wondering
> if I could add a 8k by 8 ram chip (I think something like the
> 27C64...)? I'm planning on doing some wirewrapping with the
> experiments, and have a ram chip and eeprom I'd like to add.
> Is it easy to multiplex the address and data to and from the chip?
>
> Thanks,
>
> Art
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the
> Subject and Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to
> http://docs.yahoo.com/info/terms/
>
Could you tell us where one could find some serial RAM devices and
any info on how to interconnect to Basic Stamp.
Thanks,
Vince
--- In basicstamps@y..., "Al Williams" <alw@a...> wrote:
> Hi Art,
>
> The Stamp doesn't have an external address and data bus. You'd have
to
> treat the device as an external I/O device and tie up lots of pins.
They
> do make serial EEPROMs that work well (although not very speedy).
There
> are a few serial RAM products out there as well.
>
> If you wanted to use a 27C64 (a EEPROM) and you only wanted to
access it
> sequentially, you could connect a counter like a 4040 to two I/O
pins
> (clock and clear). This would generate your address (might need to
> cascade to get the correct number of bits). Then you'd also need 8
bits
> for data (tie OE permanently low). So then you could pulse the
counter
> to read the next address. I have a EPROM programmer that works like
> that.
>
> Good luck!
>
> Al Williams
> AWC
> * Easy RS-232 Prototyping
> http://www.al-williams.com/awce/rs1.htm
>
>
> >
Original Message
> > From: Art Burke [noparse][[/noparse]mailto[noparse]:p[/noparse]ianomanab@s...]
> > Sent: Thursday, November 29, 2001 8:02 AM
> > To: basicstamps@y...
> > Subject: [noparse][[/noparse]basicstamps] Adding a ram chip-Help!!!
> >
> >
> > Hi to all:
> >
> > I've just ordered a board and the Bs2sx and am wondering
> > if I could add a 8k by 8 ram chip (I think something like the
> > 27C64...)? I'm planning on doing some wirewrapping with the
> > experiments, and have a ram chip and eeprom I'd like to add.
> > Is it easy to multiplex the address and data to and from the chip?
> >
> > Thanks,
> >
> > Art
> >
> >
> > To UNSUBSCRIBE, just send mail to:
> > basicstamps-unsubscribe@y...
> > from the same email address that you subscribed. Text in the
> > Subject and Body of the message will be ignored.
> >
> >
> > Your use of Yahoo! Groups is subject to
> > http://docs.yahoo.com/info/terms/
> >
(http://www.solutions-cubed.com/products_main.htm I think). There must
be more, but off hand I don't know of any. Many of our PAKs add a small
amount of accessible RAM, but not like a full chip's worth.
Al Williams
AWC
* Easy RS-232 Prototyping
http://www.al-williams.com/awce/rs1.htm
>
Original Message
> From: vincent.mansueto@s...
> [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=wmufQsDm27-Da2nRjLi_D31H4IMAJZL7D3ovVrLaq_c9Io6XECICLm8aHQYV1vRxrxkh4yLiPUaDDs17eVenkkCPLN8O]vincent.mansueto@s...[/url
> Sent: Thursday, November 29, 2001 12:17 PM
> To: basicstamps@yahoogroups.com
> Subject: [noparse][[/noparse]basicstamps] Re: Adding a ram chip-Help!!!
>
>
> Hello Al,
>
> Could you tell us where one could find some serial RAM devices and
> any info on how to interconnect to Basic Stamp.
>
> Thanks,
>
> Vince
>
> --- In basicstamps@y..., "Al Williams" <alw@a...> wrote:
> > Hi Art,
> >
> > The Stamp doesn't have an external address and data bus. You'd have
> to
> > treat the device as an external I/O device and tie up lots of pins.
> They
> > do make serial EEPROMs that work well (although not very speedy).
> There
> > are a few serial RAM products out there as well.
> >
> > If you wanted to use a 27C64 (a EEPROM) and you only wanted to
> access it
> > sequentially, you could connect a counter like a 4040 to two I/O
> pins
> > (clock and clear). This would generate your address (might need to
> > cascade to get the correct number of bits). Then you'd also need 8
> bits
> > for data (tie OE permanently low). So then you could pulse the
> counter
> > to read the next address. I have a EPROM programmer that works like
> > that.
> >
> > Good luck!
> >
> > Al Williams
> > AWC
> > * Easy RS-232 Prototyping http://www.al-williams.com/awce/rs1.htm
> >
> >
> > >
Original Message
> > > From: Art Burke [noparse][[/noparse]mailto[noparse]:p[/noparse]ianomanab@s...]
> > > Sent: Thursday, November 29, 2001 8:02 AM
> > > To: basicstamps@y...
> > > Subject: [noparse][[/noparse]basicstamps] Adding a ram chip-Help!!!
> > >
> > >
> > > Hi to all:
> > >
> > > I've just ordered a board and the Bs2sx and am wondering
> > > if I could add a 8k by 8 ram chip (I think something like the
> > > 27C64...)? I'm planning on doing some wirewrapping with the
> > > experiments, and have a ram chip and eeprom I'd like to add.
> > > Is it easy to multiplex the address and data to and from the chip?
> > >
> > > Thanks,
> > >
> > > Art
> > >
> > >
> > > To UNSUBSCRIBE, just send mail to:
> > > basicstamps-unsubscribe@y...
> > > from the same email address that you subscribed. Text in the
> > > Subject and Body of the message will be ignored.
> > >
> > >
> > > Your use of Yahoo! Groups is subject to
> > > http://docs.yahoo.com/info/terms/
> > >
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the
> Subject and Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to
> http://docs.yahoo.com/info/terms/
>
I've recently designed a serial RAM device. It will store 32,000
bytes of SRAM and 500 bytes of EEPROM (rated for 100,000 write
cycles). It also has a connector for a 4x3 matrix keypad for
input. The keypad is buffered (128 key presses) and the stamp can
download the keys whenever it wants. The serial input is also
buffered so you can send many commands at once without worrying
about the board losing data. If you don't use a keypad, you can use
it's 128-byte buffer as FIFO memory.
I would eventually like to sell this through a retailer like
Parallax but at the moment I don't think I can produce them in large
enough quantities. With the holidays coming up my finances are
getting very limited.
If you would like more information on this board, please send me an
email at pyromaneyakk@h...
--- In basicstamps@y..., vincent.mansueto@s... wrote:
> Hello Al,
>
> Could you tell us where one could find some serial RAM devices and
> any info on how to interconnect to Basic Stamp.
>
> Thanks,
>
> Vince
>
> --- In basicstamps@y..., "Al Williams" <alw@a...> wrote:
> > Hi Art,
> >
> > The Stamp doesn't have an external address and data bus. You'd
have
> to
> > treat the device as an external I/O device and tie up lots of
pins.
> They
> > do make serial EEPROMs that work well (although not very
speedy).
> There
> > are a few serial RAM products out there as well.
> >
> > If you wanted to use a 27C64 (a EEPROM) and you only wanted to
> access it
> > sequentially, you could connect a counter like a 4040 to two I/O
> pins
> > (clock and clear). This would generate your address (might need
to
> > cascade to get the correct number of bits). Then you'd also need
8
> bits
> > for data (tie OE permanently low). So then you could pulse the
> counter
> > to read the next address. I have a EPROM programmer that works
like
> > that.
> >
> > Good luck!
> >
> > Al Williams
> > AWC
> > * Easy RS-232 Prototyping
> > http://www.al-williams.com/awce/rs1.htm
> >
> >
> > >
Original Message
> > > From: Art Burke [noparse][[/noparse]mailto[noparse]:p[/noparse]ianomanab@s...]
> > > Sent: Thursday, November 29, 2001 8:02 AM
> > > To: basicstamps@y...
> > > Subject: [noparse][[/noparse]basicstamps] Adding a ram chip-Help!!!
> > >
> > >
> > > Hi to all:
> > >
> > > I've just ordered a board and the Bs2sx and am wondering
> > > if I could add a 8k by 8 ram chip (I think something like the
> > > 27C64...)? I'm planning on doing some wirewrapping with the
> > > experiments, and have a ram chip and eeprom I'd like to add.
> > > Is it easy to multiplex the address and data to and from the
chip?
> > >
> > > Thanks,
> > >
> > > Art
> > >
> > >
> > > To UNSUBSCRIBE, just send mail to:
> > > basicstamps-unsubscribe@y...
> > > from the same email address that you subscribed. Text in the
> > > Subject and Body of the message will be ignored.
> > >
> > >
> > > Your use of Yahoo! Groups is subject to
> > > http://docs.yahoo.com/info/terms/
> > >