Author Topic: P232 Microcontroller problem  (Read 374 times)

Mirko

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P232 Microcontroller problem
« on: January 26, 2018, 05:14:50 pm »
I bought chip P232 micontroller, I did pcb for integration hardware, I followed your schematic (you can find schematic in attached).
I have this problem,  the chip doesn't start regular, infact in the serial port there isn't flux, and the Led D1 and D2 blink in different mode rispect the P332 RDS Encoder with same chip; in the our hardware into power up D1 is off and D2 blink with different time .
can you give me some suggest ?
I have the P332 RDS Encoder this work properly.




Jan

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Re: P232 Microcontroller problem
« Reply #1 on: January 26, 2018, 05:31:38 pm »
The IC is not connected correctly but from the description I'm unable to suggest what to check.

Pettinelli Mirko

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Re: P232 Microcontroller problem
« Reply #2 on: January 26, 2018, 06:14:16 pm »
Thank you for your support, you can find in attached the schematic, i check that the hardware is connected as schematic.
Can you check if i forgot some connection ?
Seem that the microprocessor doesn't the boot or its reset.
Thank you very much

Jan

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Re: P232 Microcontroller problem
« Reply #3 on: January 26, 2018, 07:10:09 pm »
You have LED1 connected to D2 and LED2 to D1. This is confusing. So could you confirm which LED is blinking? LED1/D2 or LED2/D1?

Pettinelli Mirko

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Re: P232 Microcontroller problem
« Reply #4 on: January 26, 2018, 07:17:44 pm »
D1 is off and D2 blinks slowly but there isn't flux in the serial port and there isn't carrier RDS in output.

Jan

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Re: P232 Microcontroller problem
« Reply #5 on: January 26, 2018, 08:32:37 pm »
Please use original references for the LEDs. So LED2 never goes on and LED1 blinks? It is strange as this operational status cannot occur. The LED2 always goes on for at least 2 seconds after power up, regardless of logical value on any pin.
So the IC is either damaged (improbable) or there's other reason for malfunction (crystal/Vdd pins/Vss pins/Reset pin/Vcap pin etc.).

Also make sure that both RX pins are tied to valid RS-232 idle signal, that is +5V.

Pettinelli Mirko

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Re: P232 Microcontroller problem
« Reply #6 on: January 27, 2018, 09:45:03 am »
Thank you Jan,
Sorry Jan I mistake name of leds now i will call the pins with your indication; I have to rectify that in the pin32 (LED2) goes on for 2 second after it goes off for about 3 second after it goes on for 2 second (as if IC goes in reset) in continuous mode.
In effect in my hardware the pin 44(TX2) and pin 1(RX2) are floatting and in the pin4(TX1) and pin5(RX1) there are link the serial of the my microprocessor in TTL mode (3.3V) and now the Vdd2 is 3.3V but i can try to 5V but i don't see change.
anyway i can send you the print with oscilloscope of the pins, what do you think ?

Jan

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Re: P232 Microcontroller problem
« Reply #7 on: January 27, 2018, 08:32:34 pm »
Thanks for the clarification. The two LEDs indicate more than 10 operational states so exact description is important for quick location of the problem.
Check the I2C bus, the SDA line is probably short-circuited to ground or the EEPROM is bad or the pull-up resistor is bad.

Pettinelli Mirko

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Re: P232 Microcontroller problem
« Reply #8 on: January 29, 2018, 08:37:53 am »
Thank you Jan,
I saw in data sheet that the eeprom can be optional, andi have forecast this possibility but in this moment i don't montage eeprom, therefore the I2c pins are flotting.
must I connect they ?

Jan

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Re: P232 Microcontroller problem
« Reply #9 on: January 29, 2018, 08:47:34 am »
So finally your circuit is not as drawn on your schematic?
At least the pull-up resistor on the SDA line is necessary. The SDA line can never be left floating.
Without the EEPROM, the device will not start to generate RDS signal until you enable it by command RDSGEN=1

Pettinelli Mirko

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Re: P232 Microcontroller problem
« Reply #10 on: January 29, 2018, 09:34:52 am »
Great Jan,
Now it's work properly !!!!
Please Can you send me the description of the led1 status ?
Thank you very much !!
If this project go to well i need many pieces 
Regards

Jan

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Re: P232 Microcontroller problem
« Reply #11 on: January 30, 2018, 09:54:43 am »
The LED status indication is described in section 13.2 of the Technical manual.