UART from CPU and Hyper terminal not working right.

[ezflyr]

Hi,

Your description is not clear, so let me attempt to summarize:

1. If you connect to the 'hardware' UART pins, you can send data TO HyperTerminal, but you cannot receive data FROM HyperTerminal using PCM's simple program? Is that correct?

2. If you connect to some other pins (ie. a 'software' UART), you can send data TO HyperTerminal, AND you can receive data FROM HyperTerminal using PCM's simple program? Is that correct?

If the above is correct, we need to know if your USB-to-TTL converter is the *exact* one shown in the link you provided, or a similar one??? We also need to know the Vcc voltage of your PIC.

My hunch is that this is a level issue at the hardware UART Rx pin, that is not an issue with a software Rx input.

Finally, what is your compiler version number?
_________________
John

If it's worth doing, it's worth doing in real hardware!

[temtronic]

I downloaded the linked datasheet...

THAT USB device is NOT going to work by simply connecting to your PIC!

The datasheet says it's an RS232 style unit , so it expects to be connected to a MAX232 or simlar RS232 device. The PIC is a 'TTL' device.

Options.
1) buy a TTL<>USB module. Up here they're $2.

2) add a MAX232 + 4 caps between PIC and the RS232-USB module.

Either of these options will work.

Jay

[ezflyr]

Hi Jay,

I suspect that link does not point to the *actual* USB-to-whatever module the OP is using, that is why I asked him the question directly. In this day and age of really cheap (mostly knock-off) Chinese USB modules, the likelihood that the OP has an honest-to-goodness FTDI USB evaluation module is really pretty slim....
_________________
John

If it's worth doing, it's worth doing in real hardware!

[nailuy]

Thank you to all.
First I will response in order of replies.
ezflyr:
#1 is not correct PIC in hardware UART no sending data on pin C6 so Hiper ... not receiving data and show nothing.
#2 is half correct PIC in software UART is sending data and Hiper ... show data received. Other half I search on help of CCS about if(kbhit()) and not worked, I do not know why? request help and received from PCM programmer with little program, and discover that data not sending with hardware UART. I can tell that: data send from Hiper ... is entering to PIC (I see with scope) and PIC do nothing with simple test program. I can't confirm that PIC is receiving data in buffer because if(kbhit()) never becomes true not in software not in hardware.
Also if I change software UART with the same pins as hardware is not working.
I test simple output high/low C6 and is working so output is not burned.
I use exactly this unit UB232R as is describe in picture of page no7 UB232R datasheet
Voltage powered is 5.04V and signal logic high is at 5.03V and signal logic low is 0.02V so USB converter works fine. This measurements are made on pin C7 RX.
Version compiler 5.053

now response for temtronic
If you download data sheet of chip you will see on page 31 connection directly to Microcontroller and I use only TXD and RXD pins.
Data sheet of IC:
http://www.ftdichip.com/Support/Documents/DataSheets/ICs/DS_FT232R.pdf
Data sheet of hardware converter USB->UART TTL logic
http://www.ftdichip.com/Support/Documents/DataSheets/Modules/DS_UB232R.pdf
Conclusion:
This hardware used by me UB232R are using FT232R chip and is connecting directly to Microcontroller, also if I make short circuit between RX TX, Hiper Terminal show every key pressed so UB232R fork fine at 5V because J3 have jumper on position 1-2.
I look forward for your replies.

[temtronic]

You should post your current complete code as 'something' is not correct.

As for the module, it does say TTL way in the spec. FTDI should NOT be saying 232 anywhere as '232' inplies the RS232 standard.

Somewhere in those documents they do say about inverting the data....arrgh....also you have to program the modue using a 'dll', more fun...

You might try another PIC, that one may be damaged ? Just because the software serial transmit works does NOT mean the UART is OK

Jay

[nailuy]

Yes finally this it leads me to an outcome why?
led is not working when row "putc('H');" is enabled, when is disabled led is blinking soproblem is from heir I think not from chip or other hardware connection.
Result is the same for 1 or 4 or 8 Mhz
is working on TTL signal between USB converter and MCP.
Cod:

complete program is:

[temtronic]

When you try to send the 'H', this is where the pIC goes...
.................... #use rs232(baud=2400, UART1, ERRORS)
0003: BTFSS 11.4
0004: GOTO 003
0005: MOVLB 03
0006: MOVWF 1A
0007: MOVLP 00
0008: MOVLB 00
0009: GOTO 022 (RETURN)

BTFSS 11.4 says
test bit 4 or register 11 (PIR1) and skip if set
GOTO 3 says
loopback to 0003

It'll do this UNTIL bit 4 is a 1.
According to my copy of the 1788 manual, .4 is a pending TX interrupt...so now I'm confused as I don't see where ,if at all you've enabled ANY interrupts !
Perhaps do a 'global disable' as your compiler version may enable it ??
Hopefully someone with that PIC and close compiler version can test for you.

I'm pretty much done.
Sure be nice to KNOW what's happening though !!

Jay

[nailuy]

I do not have any interrupts enabled or disabled in program.
How can I make global disabled interrupt?
Best regards.

[temtronic]

disable_interrupts(GLOBAL); // all interrupts OFF

this is covered in the CCS C manual, just press f11 while your project is open, and the manual will appear !

Jay