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connecting from usb to serial problem

Hi, I have a ppc (405 ep) based chamelon dev kit. I wanted to re-use it after long time ago. First i noticed that i do not have a serial interface on my board, so i bought serial-to-usb connector, Then noticed that the both side of serial-to-usb's and boards serial connecter's output is male, i found a cable which has female connectors on both sides. I connected my board and my pc via plugged- in this long cable, i successfully receive messages from pretty old board but then i noticed that i cannot type anything! actually i can type but when pressed to a character, non-related and randomly some weird character(s) appear, if i am lucky by pressing enter several times to enter, i can send my command. example output;

(I'm trying to type hello here)

CPU: IBM PowerPC 405EP Rev. B at 333.333 MHz (PLB=3D111, OPB=3D55, EBC=3D37 MHz) +----------------------------------------+ IIC Boot EEPROM disabled PCI async ext clock used, internal PCI arbiter enabled 16 kB I-Cache 16 kB D-Cache Board: ### No HW ID - assuming PPChameleonEVB I2C: ready DRAM: 32 MB FLASH: 4 MB PCI: Bus Dev VenId DevId Class Int Video: Controller not found ! NAND: 32 MB =3D> i=EF=BF=BD=EF=BF=BD=EF=BF=BD=EF=BF=BD=EF=BF=BDi=EF=BF=BD=EF=BF=BDl=EF= =BF=BD=EF=BF=BDM=EF=BF=BD=EF=BF=BD=EF=BF=BD

i tried in both using minicom and cu and linux recognizes the connector as /dev/ttyUSB0.My connection scheme

PPC rs232 male Computers USB port

What can be a problem?

Thanks.

Reply to
Sinan
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Your baud rate seems to ok (otherwise you wouldn't see the characters). First of all make sure your rs232ToUSB converter is working solid for the given baud rate. Use it with another computer using a cross-over cable and make sure the you can get reliable reads and writes. Secondly make sure your FemaleToFemale cable connectivity is good using a multimeter. Thirdly check your Parity and handshaking settings.

Reply to
Janaka

Thanks for the answer.

Reply to
Sinan

Here's a basic trick to check serial ports: short the Tx and Rx pins; you should see echo when typing. I have a magic paperclip in my drawer that handles ejecting CDroms/floppies, and shorting female and even male DB connectors (it helps that Tx and Rx are next to each other, e.g. pins

2 and 3 on a DB25 RS232) 
--
		Przemek Klosowski, Ph.D.
Reply to
przemek klosowski

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