Google Groups no longer supports new Usenet posts or subscriptions. Historical content remains viewable.
Dismiss
chip 733w01522 what is it?
94 views
Skip to first unread message
Enrico Lazzerini
Apr 4, 2013, 12:42:47 PM4/4/13
to
Is there anybody who knows what is this old chip? And where to try to find
it?
If it help what I know is that it used to do somenting like shift data
register or Serial Shift Registers.
It has a TTL level signal on its pins, it has 14 pins. You can see it named
U1 in the centre of this schematic:
https://www.dropbox.com/s/zqhgar4g7ib5j4z/Xerox820_FDC_Schematic.pdf
Some pins are labelled on a schematics with:
1=D1, 2=D2, 3=D3, 4=D4,
10=A1, 11=A2, 12=A3, 13=A4, 14=A4,
15=ChipEnable (left to GND),
7=GND,
14=+5Vcc
Thanks
--- news://freenews.netfront.net/ - complaints: ne...@netfront.net ---
it?
If it help what I know is that it used to do somenting like shift data
register or Serial Shift Registers.
It has a TTL level signal on its pins, it has 14 pins. You can see it named
U1 in the centre of this schematic:
https://www.dropbox.com/s/zqhgar4g7ib5j4z/Xerox820_FDC_Schematic.pdf
Some pins are labelled on a schematics with:
1=D1, 2=D2, 3=D3, 4=D4,
10=A1, 11=A2, 12=A3, 13=A4, 14=A4,
15=ChipEnable (left to GND),
7=GND,
14=+5Vcc
Thanks
--- news://freenews.netfront.net/ - complaints: ne...@netfront.net ---
Michael Haardt
Apr 4, 2013, 2:09:27 PM4/4/13
to
The schematic is hard to read, but it looks like a 74S288, which is
a TTL PROM. That would match its usage.
Michael
a TTL PROM. That would match its usage.
Michael
Bill Gunshannon
Apr 4, 2013, 2:22:55 PM4/4/13
to
In article <515dc1d7$0$1684$bb62...@newsread.freenet.ag>,
says pin 16. Oh wait, he has pin 14 listed twice. I vote for 74S288. :-)
bill
--
Bill Gunshannon | de-moc-ra-cy (di mok' ra see) n. Three wolves
bill...@cs.scranton.edu | and a sheep voting on what's for dinner.
University of Scranton |
Scranton, Pennsylvania | #include <std.disclaimer.h>
mic...@moria.de (Michael Haardt) writes:
> The schematic is hard to read, but it looks like a 74S288, which is
> a TTL PROM. That would match its usage.
>
I thought the same thing except he said Vcc was on pin 14 and the datasheet
> The schematic is hard to read, but it looks like a 74S288, which is
> a TTL PROM. That would match its usage.
>
says pin 16. Oh wait, he has pin 14 listed twice. I vote for 74S288. :-)
bill
--
Bill Gunshannon | de-moc-ra-cy (di mok' ra see) n. Three wolves
bill...@cs.scranton.edu | and a sheep voting on what's for dinner.
University of Scranton |
Scranton, Pennsylvania | #include <std.disclaimer.h>
glen herrmannsfeldt
Apr 4, 2013, 4:21:28 PM4/4/13
to
Michael Haardt <mic...@moria.de> wrote:
> The schematic is hard to read, but it looks like a 74S288, which is
> a TTL PROM. That would match its usage.
Is this the lookup table for precompensation?
> The schematic is hard to read, but it looks like a 74S288, which is
> a TTL PROM. That would match its usage.
By the time I got into FDCs, they were all in MOS LSI and those
details weren't needed.
-- glen
David Schultz
Apr 4, 2013, 5:52:19 PM4/4/13
to
Western Digital 179X application note. (Page 206 in my copy of the 1983
handbook.) But different enough so that the PROM data table might not be
the same.
That schematic identifies it as a 745288 PROM.
--
David W. Schultz
http://home.earthlink.net/~david.schultz
Returned for Regrooving
glen herrmannsfeldt
Apr 4, 2013, 7:17:01 PM4/4/13
to
David Schultz <ab...@127.0.0.1> wrote:
> On 04/04/2013 01:09 PM, Michael Haardt wrote:
>> The schematic is hard to read, but it looks like a 74S288, which is
>> a TTL PROM. That would match its usage.
>> Michael
>>
> That part of the circuit looks remarkable like the data separator in the
> Western Digital 179X application note. (Page 206 in my copy of the 1983
> handbook.) But different enough so that the PROM data table might not be
> the same.
> That schematic identifies it as a 745288 PROM.
Looks like an OCR error for 74S288.
> On 04/04/2013 01:09 PM, Michael Haardt wrote:
>> The schematic is hard to read, but it looks like a 74S288, which is
>> a TTL PROM. That would match its usage.
>> Michael
>>
> That part of the circuit looks remarkable like the data separator in the
> Western Digital 179X application note. (Page 206 in my copy of the 1983
> handbook.) But different enough so that the PROM data table might not be
> the same.
> That schematic identifies it as a 745288 PROM.
-- glen
Bill Gunshannon
Apr 4, 2013, 8:27:35 PM4/4/13
to
In article <oCm7t.68153$_R.3...@en-nntp-16.dc1.easynews.com>,
> Western Digital 179X application note. (Page 206 in my copy of the 1983
> handbook.) But different enough so that the PROM data table might not be
> the same.
>
> That schematic identifies it as a 745288 PROM.
That's an "S", not a "5".
David Schultz <ab...@127.0.0.1> writes:
> On 04/04/2013 01:09 PM, Michael Haardt wrote:
>> The schematic is hard to read, but it looks like a 74S288, which is
>> a TTL PROM. That would match its usage.
>>
>> Michael
>>
>
> That part of the circuit looks remarkable like the data separator in the
I thought so, too.
> On 04/04/2013 01:09 PM, Michael Haardt wrote:
>> The schematic is hard to read, but it looks like a 74S288, which is
>> a TTL PROM. That would match its usage.
>>
>> Michael
>>
>
> That part of the circuit looks remarkable like the data separator in the
> Western Digital 179X application note. (Page 206 in my copy of the 1983
> handbook.) But different enough so that the PROM data table might not be
> the same.
>
> That schematic identifies it as a 745288 PROM.
Enrico Lazzerini
Apr 9, 2013, 1:58:03 PM4/9/13
to
I'm here again. Sorry for the late. ALl of you are right. The is is a
74S288 PRO 16 pin used with 74LS174 as finite state machine. in the 1797
application notes there is at page 12 the exact scheme and.. the list of
code to inert into that 74S288. i not trust so much in thos old application
notes and i have not any programmed 74S288 to read (really i not know how
to do this) so i prefer not realize this kind of schematic.
i found instead this one:
https://www.dropbox.com/s/4f8kblogrlzdr9m/FDC_from_Micro_Cornucopia_%2322_Feb85.pdf
that seems so better and i'm lucky cause i have also a working spare kaypro
II motherboard so i could use ist tested compontent.
BUT
where to find it?
buying from italy to us: about 7 USD + shipping 28USD for 1 only
buying in europe: 6USD + shipping but (ten at times)
is there anybody who could give me other suggestions also using other old
way like reusing obsolete part of computers)
Thnks for any suggestion.
Enrico - Italy
74S288 PRO 16 pin used with 74LS174 as finite state machine. in the 1797
application notes there is at page 12 the exact scheme and.. the list of
code to inert into that 74S288. i not trust so much in thos old application
notes and i have not any programmed 74S288 to read (really i not know how
to do this) so i prefer not realize this kind of schematic.
i found instead this one:
https://www.dropbox.com/s/4f8kblogrlzdr9m/FDC_from_Micro_Cornucopia_%2322_Feb85.pdf
that seems so better and i'm lucky cause i have also a working spare kaypro
II motherboard so i could use ist tested compontent.
BUT
where to find it?
buying from italy to us: about 7 USD + shipping 28USD for 1 only
buying in europe: 6USD + shipping but (ten at times)
is there anybody who could give me other suggestions also using other old
way like reusing obsolete part of computers)
Thnks for any suggestion.
Enrico - Italy
Enrico Lazzerini
Apr 23, 2013, 4:11:33 PM4/23/13
to
I Thanks for you suggestions, the question has been solved.
Trying to rebuild the FDC card for my xerox 820-II motherboard, I have
discovered the presence of an IC named 733w01522 (U1) on the photo of the
original PCB which code I cannot read on the schematic not very readable
reported at the end of xerox820-II service manual. Sorry, I mistakenly
indicated a 14-pin TTL chips even though it was 16 pin.
Thanks for contribution of MIKES from the VCF he told me that the
733w01522 chip is a PROM and it is equivalent at 74S288 but also to others
IC as
reported here http://www.hobbyroms.com/proms.html by Chuck.
U1 (74S28 and U2 (74S174) together constitute a "finite state machine" (so
they told to me cause I'm not so expert) whose purpose is to provide a read
clock and a read data to the chip WD1797 from raw data received from the
drive.
Then I need to discover the code that the chip could have recorded itself
(without having the original chip programmed with me!).
Upon the recommendation of Chuck Guzis I found the code listing on page 12
of the manual of the FDC1797's application notes. At this point, trusting
to
this code I'd need to buy a programmed 74S288 (or equivalent).
There is another problem : a delay network U16=0447-0400-02
(https://www.dropbox.com/s/l4wxp3hdsf...47-0400-02.pdf )
After all those news, I was finally trying to figure out if it sould be
better to
use of the schematic published on an old issue of Microcornucopia:
https://www.dropbox.com/s/4f8kblogrlzdr9m/FDC_from_Micro_Cornucopia_#22_Feb85.pdf
Who wrote that so far article decided to build itself a FDC controller card
for his
xerox 820-II extracting a block of its schematic from a Kaypro-II's
schematic really making very few changes and using a FDC WD1793 + WD9216
for
external separator data. Casually i have a socketed spare working kaypro-II
motherboard
Due to its small number of components, and having already a WD1797 +
WD921I'd just
and wiring that schematic it would be maybe more simple.
I'm waiting to receive a Vector plugboard 36+36 pin
http://www.ebay.com/itm/ws/eBayISAPI...m=200797705856 while I hope to be
able to buy
a day a ready Xerox 820-II FDC board even I know that it's not very easy to
find.
Thanks anyway for all the support that was given to me.
Regards
Enrico - Pisa (ITALY)
Trying to rebuild the FDC card for my xerox 820-II motherboard, I have
discovered the presence of an IC named 733w01522 (U1) on the photo of the
original PCB which code I cannot read on the schematic not very readable
reported at the end of xerox820-II service manual. Sorry, I mistakenly
indicated a 14-pin TTL chips even though it was 16 pin.
Thanks for contribution of MIKES from the VCF he told me that the
733w01522 chip is a PROM and it is equivalent at 74S288 but also to others
IC as
reported here http://www.hobbyroms.com/proms.html by Chuck.
U1 (74S28 and U2 (74S174) together constitute a "finite state machine" (so
they told to me cause I'm not so expert) whose purpose is to provide a read
clock and a read data to the chip WD1797 from raw data received from the
drive.
Then I need to discover the code that the chip could have recorded itself
(without having the original chip programmed with me!).
Upon the recommendation of Chuck Guzis I found the code listing on page 12
of the manual of the FDC1797's application notes. At this point, trusting
to
this code I'd need to buy a programmed 74S288 (or equivalent).
There is another problem : a delay network U16=0447-0400-02
(https://www.dropbox.com/s/l4wxp3hdsf...47-0400-02.pdf )
After all those news, I was finally trying to figure out if it sould be
better to
use of the schematic published on an old issue of Microcornucopia:
https://www.dropbox.com/s/4f8kblogrlzdr9m/FDC_from_Micro_Cornucopia_#22_Feb85.pdf
Who wrote that so far article decided to build itself a FDC controller card
for his
xerox 820-II extracting a block of its schematic from a Kaypro-II's
schematic really making very few changes and using a FDC WD1793 + WD9216
for
external separator data. Casually i have a socketed spare working kaypro-II
motherboard
Due to its small number of components, and having already a WD1797 +
WD921I'd just
and wiring that schematic it would be maybe more simple.
I'm waiting to receive a Vector plugboard 36+36 pin
http://www.ebay.com/itm/ws/eBayISAPI...m=200797705856 while I hope to be
able to buy
a day a ready Xerox 820-II FDC board even I know that it's not very easy to
find.
Thanks anyway for all the support that was given to me.
Regards
Enrico - Pisa (ITALY)
glen herrmannsfeldt
Apr 23, 2013, 5:42:08 PM4/23/13
to
Enrico Lazzerini <enr...@vintagesbc.it> wrote:
(snip)
Normally they are sold unprogrammed.
> After all those news, I was finally trying to figure out if it
> sould be better to use of the schematic published on an old
> issue of Microcornucopia:
> https://www.dropbox.com/s/4f8kblogrlzdr9m/FDC_from_Micro_Cornucopia_#22_Feb85.pdf
> Who wrote that so far article decided to build itself a FDC
> controller card for his xerox 820-II extracting a block of its
> schematic from a Kaypro-II's schematic really making very few
> changes and using a FDC WD1793 + WD9216 for external separator
> data. Casually i have a socketed spare working kaypro-II motherboard
As well as I remember from the 1793 days, analog data separators
were considered to work much better than digital ones.
-- glen
(snip)
> Then I need to discover the code that the chip could have recorded itself
> (without having the original chip programmed with me!).
> Upon the recommendation of Chuck Guzis I found the code listing on
> page 12 of the manual of the FDC1797's application notes.
> At this point, trusting to
> this code I'd need to buy a programmed 74S288 (or equivalent).
> There is another problem : a delay network U16=0447-0400-02
> (https://www.dropbox.com/s/l4wxp3hdsf...47-0400-02.pdf )
I am not sure now how hard it is to program the 74S288.
> (without having the original chip programmed with me!).
> Upon the recommendation of Chuck Guzis I found the code listing on
> page 12 of the manual of the FDC1797's application notes.
> At this point, trusting to
> this code I'd need to buy a programmed 74S288 (or equivalent).
> There is another problem : a delay network U16=0447-0400-02
> (https://www.dropbox.com/s/l4wxp3hdsf...47-0400-02.pdf )
Normally they are sold unprogrammed.
> After all those news, I was finally trying to figure out if it
> sould be better to use of the schematic published on an old
> issue of Microcornucopia:
> https://www.dropbox.com/s/4f8kblogrlzdr9m/FDC_from_Micro_Cornucopia_#22_Feb85.pdf
> Who wrote that so far article decided to build itself a FDC
> controller card for his xerox 820-II extracting a block of its
> schematic from a Kaypro-II's schematic really making very few
> changes and using a FDC WD1793 + WD9216 for external separator
> data. Casually i have a socketed spare working kaypro-II motherboard
were considered to work much better than digital ones.
-- glen
Steven Hirsch
Apr 24, 2013, 7:54:19 AM4/24/13
to
On 04/23/2013 05:42 PM, glen herrmannsfeldt wrote:
supply programmed bipolar PROMs for a nominal fee.
Very few device programmers can handle these old parts.
> Enrico Lazzerini <enr...@vintagesbc.it> wrote:
>> this code I'd need to buy a programmed 74S288 (or equivalent).
>> this code I'd need to buy a programmed 74S288 (or equivalent).
> I am not sure now how hard it is to program the 74S288.
> Normally they are sold unprogrammed.
There is at least one vendor catering to arcade game enthusiasts who will
> Normally they are sold unprogrammed.
supply programmed bipolar PROMs for a nominal fee.
Very few device programmers can handle these old parts.
0 new messages