Thanks for your fast reply. I just received the MAX 232 chip yesterday and i tried to control the pump according to the advises this morning. I'm now using a Audrino Mega 2560 as i need quite a lot of digital pins and serial pins to control other TTL devices later on.
After trying few different options, i failed to receive any responses from the pump. I hope that i'm able to receive some simple sketch example from you based on the information below.
"i'm using Mega Serial3(Tx3 pin14,Rx3 pin15) as the serial pin to connect to the Max232 chip(pin 11&12) and from pin 13&14 of Max232 connect directly to the pump RS232 (Txd,Rxd)pin and grounded.
The pump can be controlled by Hyperterminal (tested and it work but i hope that i can directly use the audrino platform to control all my other devices) with these settings: Baud rate:9600, Databits:8, parity:none, stopbits: 1, flow control:none. The command is base on the ASCll. One of the example of command to initiate the pump is /1W4R
As i'm totally a newbie with limited knowledge on the Audrino programming, It will be a great help if any of you able to show me a simple example how should i write the sketch. I'll keep on trying at the mean time and thanks in advance.