oneWire and CY8C21345

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GeMo_285911
Level 4
Level 4
First like received

Hello,

   

  I am working on a small project, that requires the reading and display of a DS18B20 sensor. I searched for a small chip, and I bought the CY8C21345. However, when I started working with it, I foud out that there is no OneWire component in the components list. Is there any bit banging program for this protocol that can be implemented with the M8C (I have it working on PSoC 3, but not for PSoC 1)? From what I have seen, the smallest delay you can get here is 50u. Can you generate the code from the component found on ther PSoC 1 chip?

   

Thank you!

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8 Replies
ArvindK_86
Employee
Employee
10 sign-ins 5 sign-ins 10 solutions authored

Hello,

   

 

   

The Onewire usermodule should be there! As per the v1.1 datasheet Onewire is supported in the following PSoC1 devices -

   

CY8C29/27/24/23/21xxx, CY8CLED02/04/08/16, CY8CLED0xD, CY8CLED0xG, CY8C28x45, CY8CPLC20, CY8CLED16P01, CY8C28xxx. We'll check on this and fix it in the next update PSoC Designer.

   

 

   

Regards,

   

Arvind

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ETRO_SSN583
Level 9
Level 9
250 likes received 100 sign-ins 5 likes given

Frtom datasheet shows support for 21xxx -

   

 

   

OneWire Datasheet OneWire V 1.1

   
    
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            

Resources

PSoC® Blocks

API Memory (Bytes)

Pins (per External I/O)

Digital

Analog CT

Analog SC

Flash

RAM

CY8C29/27/24/23/21xxx, CY8CLED02/04/08/16, CY8CLED0xD, CY8CLED0xG, CY8C28x45, CY8CPLC20, CY8CLED16P01, CY8C28xxx

Main UM

2

0

0

168

1

2

+ Optional CRC16

0

0

0

43

2

0

+ Optional Search

0

0

0

618

11

0

+ Optional Overdrive Speed

0

0

0

45

1

0

+ Optional Parasite Power

0

0

0

42

1

0

    
   
   
              

Features and Overview

   
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GeMo_285911
Level 4
Level 4
First like received

Here is a screenshot of my project's layout. I cannot find OneWire there.

   

Thanks!

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ETRO_SSN583
Level 9
Level 9
250 likes received 100 sign-ins 5 likes given

Why dont you file a CASE on this, seems like it may be an

   

error. Might be able to import the module into design, ask

   

if thats possible. Use a link to your post.

   

 

   

    

   

          

   

To create a technical or issue case at Cypress -

   

 

   

www.cypress.com

   

“Support”

   

“Technical Support”

   

“Create a Case”

   

 

   

You have to be registered on Cypress web site first.

   

 

   

Regards, Dana.

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ArvindK_86
Employee
Employee
10 sign-ins 5 sign-ins 10 solutions authored

 Hi,

   

 

   

Apologies for the previous, it looks like the OneWire v1.1 datasheet is not accurate..

   

 

   

Instead of   CY8C21xxx, it should read CY8C21x34, this is the only device currently suported in that series.

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GeMo_285911
Level 4
Level 4
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Thank you for your replies. Do you know, is there any bit banging solution for one wire in PSoC 1?

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ETRO_SSN583
Level 9
Level 9
250 likes received 100 sign-ins 5 likes given

Take a look at this, and references at bottom for solutions -

   

 

   

    

   

          http://en.wikipedia.org/wiki/1-Wire

   

 

   

Regards, Dana.

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GeMo_285911
Level 4
Level 4
First like received

Thank you! It works.

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