Sequential (138) GSM

https://johnchihau.blogspot.com/2026/05/january-31-1995-u.html?m=1 

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Ref: https://johnchihau.blogspot.com/2026/04/john-eddy-is-person-in-this-link.html?m=1

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John : This article mention about the architecture of read and write.  https://chihaukam.blogspot.com/2024/08/have-look.html?m=1 . You might take a look at it first. 

Me: Ok.

John : There's a Tri-state buffer zone.  When the Tri-state buffer zone is 1, output is available else output is unavailable. 

Me: Ok.

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John : Now, take a look at the Pic above.  It's a GSM circuit.  

Me: It's used in Mobile phone. 

John: Yes, do you see the RTS (Ready to send)?

Me: Yes,

John : In fact, RTS (Ready to send) act as a Tri-state buffer zone.  In code it is,

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While (The Clock line of the GSM Antenna is running)

{

If (RTS = 1)

{

TXD = True; // TXD stand for transmission. 

}

else 

{

TXD = false; 

}

}
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