Application notes - HTML

SIMEPROM-02, serial communication, problem description and solution

This note is applicable to SIMEPROM-02 (obsolete), not to SIMEPORM-02aLV!

Lately its occurred some problems concerning SIMEPROM-02 <--> PC connection through serial port. Failure is appear only occasionally with the PC, there have peripheral chips integrated on the motherboard. In this cases is communication drop-outs occurred or communication is missing. Reason of this is other way of serial data recognition in this latest serial/parallel converter chips.

Below mentioned adjustment of the communications cable SIMEPORM-02 / PC solve this problem fully and with minimal material/people/time costs. If you haven't time or don't like make this adjustment yourself, cable can be send to us or ours distributor. Sure, we make this changes free.

Simulators from serial number 13287 are delivered without above mentioned problem. If occurs no problem at all of PC, currently used with your SIMEPROM-02, all this can be ignored.

If any problems occurred, please, don't hesitate to contact us any way.

Used parts:
  • resistor 1k2, 5%, standard or SMT, 1pc
  • capacitor 10nF, 20%, 1pc
  • Si diode 40V/200mA, e.g. 1N4148, 1pc

Adjustment description:
  • remove cover from DSUB25 (CANNON 25 female)
  • set position of DSUB25 connector with SMT side above and connection cable left
  • remove SMT resistor 270R (labeled 271) by solding both ends of resistor simultaneously
  • instead 270R resistor (at the same place) to sold resistor 1K2 (on the pict. 3 is shown application of standard resistor)
  • parallel on the resistor sold the diode, anode on the pin 1 of optron H11L1, cathode downward
  • nip in the rest of pins over the SMT side of PCB to avoid of capacitor's coating damage
  • between terminals 1 and 2 of H11L1 optron to solder capacitor 10nF