3 Replies Latest reply on Apr 13, 2017 12:14 AM by raviphulsundar_2366941

CY8CKIT-042: UART problem

raviphulsundar_2366941 Aug 18, 2017 2:56 PM

Dear All,

I am trying to develop MODBUS SLAVE on CY8CKIT-042 board. I have written simple program initially to transmit whatever received. Code works when I type on Hyper terminal nicely. But when I send MODBUS frame through Modbus testing software (I tried two diff. s/w), software gets hang.

When I shorts two pins (RX- P0_4, Tx- P0_5) on PSoC 5LP I/O Header (J8) , board transmits whatever I types on Hyperterinal. But Modbus testing softwares gets hang.. Testing software works fine on PC UART ports.

What could be the problem ?

Thanx in advance

Ravi

1. Re: CY8CKIT-042: UART problem

user_411084576 Apr 10, 2017 2:51 AM (in response to raviphulsundar_2366941)

Hi Ravi,

Please attach your project so that we can have a look into it.
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2. Re: CY8CKIT-042: UART problem

raviphulsundar_2366941 Apr 11, 2017 2:32 AM (in response to raviphulsundar_2366941)
Dear Embedd Holmes, Thanx for reply.

I have connected PC USB port to USB Connector (J10) onj board. And trying to do serial communication through this KitProg USB-UART port.

Plz find the attached project which works well. Program reply the same char for every received character.

However when I send stream of bytes through MODBUS testing software like Modscan32, ModbusTester, etc., these testing software gets hang. Same testing softwares work fine when connected on other COM port on PC.

One thing I observed recently is if I short P12_7 & P12_6(bypassing pSoc4) , same problem persist.

That means, there may be some pbm from PSoC 5LP Programmer & Debugger.

UART1.cywrk_.Archive01.zip 1.3 MB
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3. Re: CY8CKIT-042: UART problem

raviphulsundar_2366941 Apr 13, 2017 12:14 AM (in response to raviphulsundar_2366941)

Dear Embedd Holmes,,

My guess was correct, problem is in PSoC 5LP circuit.

I took out Tx(P0_5) & Rx(P0_4) from pSoC4 CPU and connected externally to MAX232 IC and connected to Computer.

My program is now working as expected.
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