Question : Problem: RS232 max current

How many Ampere can i have from the DTR and RTS pins of a RS232?

(this problem is related to the Nokia Data suite serial cable, you can find a scheme at
http://gsm-cables.com/nokia/cables.html.
I'v build the cable, but when i plug it in the COM, i have only 4.8V on the RTS and DTR wires. I think i ask too much current)
100 pts bonus if you can solve my cable problem!

Answer : Problem: RS232 max current

>>i have only 4.8V on the RTS and DTR wires. I think i ask too much current)

You're talking of voltage, which has nothing to see with current.

There are some brands/models of tablets/digitizer which are fed directly from serial port.

Typical UART (the RS-232 I/O chip) allows up to 50 mA per output pin, so if your device needs 70 mA to run you will need to use at least 2 pins for power.