[mmodeler]

I am trying to DNC a large program at 19200 baud rate and the buffer fills. At that point the handshake between machine and computer loses information and a error is the result. I am using a RS232 cable about 20' long. Anybody seen this?

[lkenney]

slow your baud rate down so the machine can stay ahead of the data flow.

[CNC Viking]

mmodeler,

I have a 1996 Feeler FV-800 with Mitsubishi Meldas 520 AM control and have no problem drip feeding at 19 200 Baud with a 20' serial cable between my PC and the front panel. Remember that there is also a 22' internal intermediate cable from the front panel to the control at the back. Total L=42' !

I have the CNC parameters set to Hardware (RTS/CTS) handshake:

PARAMETER 1
#. Parameter input (value)
2. Baud rate: 0 (19200 Baud)
3. Stop Bit: 3 (2 stop bits)
3. Parity Effective: 0 (No Parity bit during I/O)
5. Even Parity: 0 (Odd Parity)
6. Chr Length: 3 (8 data bits) this is a little special with Mitsubishi controls.
7. Terminator Type: 3 (EOR is fixed no matter what you choose)
11. Hand Shake: 1 (RTS/CTS Hardware)
12. DC Code Parity: 0 (No DC code parity)

PARAMETER 2
#. Parameter Input (value)
1. DC2/DC4 Output: 0 (Without DC2, without DC4)
2. CR output: 1 (On)
3. EIA Output: 0 (ISO)
4. Title Feed out: 0 (Off)
5. Feed Chr:0 (0 Characters)
6. Parity V:0 (Off)
7. Time Out:0 (0 seconds)
8. RST Ignore:0 (RST valid)

PC parameters for COM1 serial port

Baud rate: 19200
Data Bits: 7
Parity: Even
Stop Bits: 2
Flow control: Hardware
FIFO buffers in "Advanced" are set to "LOW".


DNC program parameters

Com port: COM1
Baud rate: 19200
Flow control: RTS/CTS
Code system: ISO
Data bits: 7
Parity: Even
Stop bits: 2

Serial cable pinout (20' Belden 8104 shielded low capacitance cable):

PC side 9-pin Dsub female <---> CNC side 25 pin Dsub male

2 RxD <---> 2 TxD
3 TxD <---> 3 RxD
5 Signal Ground <---> 7 Signal Ground
7 RTS <---> 5 CTS
8 CTS <---> 4 RTS

Pins 4 DTR & 6 DSR are jumpered at PC side's 9-pin Dsub female

Pins 6 DSR & 20 DTR are jumpered at CNC side's 25-pin Dsub male
Pin 8 is not used at my CNC side's 25-pin Dsub male, but may need be jumpered to 6 & 20 for your CNC. Please check this.

/ Peter

[dcoupar]

Are you wired to a com port on the PC or are you using a USB to serial adapter? Hardware handshake?

[Donkey Hotey]

I'm also wondering if the buffer is loading so much information that the PC thinks the connection was lost after a certain amount of time (waiting for the machine to respond back). Is there a time-out setting on the communication software?

[mmodeler]

I am using a com port.
Lines are being lost. the computer does not send the information fast enough I think.

[lkenney]

Drop the baud rate to 9600 on both the pc and the haas and see if the trouble continues
Eagle

[gm3211]

Also make sure you disable the FIFO on the local comm port. You could also try using RTS/CTS (hardware flow control) if you have a cable that is wired this way. If you need help still, feel free to give us a call. We have lots of experience in connecting this machine and cabling.