K8048 RS232 Issues

Kits Microcontroller Programmer - Experimenting Project
1

Hi,

Like other people, I tried using a USB/RS232 converter with K8048 and found it didn’t work.

It does work on an old, coal-fired, steam-powered laptop, running Windows '98, but I want to run it on a newer XP Pro laptop with no RS232 ports.

So, I have some questions…

  1. :?: Velleman, you mentioned (in this forum) that the K8048 does not use ‘standard’ RS232 protocol. Can you please tell me exactly which RS232 lines the kit uses, and how your signalling works - what do you use each line for?

  2. :?: Velleman, can you please tell me if K8048 should work with an RS232 PCMCIA card in a laptop running XP Professional, SP2? I’m assuming it should work (as this is similar to adding a PCI RS232 card to a normal PC), BUT I don’t want to spend £50 - £150 for a card if it won’t work.

  3. :?: Vellman, you say (in another thread) the USB incompatibility issue is mentioned (somewhere) - I can’t find any mention of this anywhere. Velleman, I’d ask that, in future, you make CLEAR, on the packaging and advertising, that USB converters won’t work. I was disappointed to find such an issue, as most PC’s/laptops no longer ship with RS232 ports.

Whilst I’ve asked Velleman, directly, about these questions, I’d be interested to hear from anyone else who has a solution to this problem.

Many thanks and Happy New Year to all.

Regards

2

The pic programmers use the handshaking lines of the RS232 port as their status is fully controllable trough software. The RX/TX lines cannot be used, as they only send/receive RS232 signals (i.e. you cannot put them in a high or low state yourself). Check the diagram of the kit for further reference regarding the used lines.

USB to serial converters tend to mess up the timing of the signals, which is quite critical for PIC programming, so they cannot be used for this purpose.

A PCMCIA card with serial port should work fine, however we have no experience with this matter so we cannot guarantee it will work.

3

Thanks, vel417

The cheapest PCMCIA I found was GBP50, so I think it’s probably less risk if I try to find a dedicated USB-based programmer.

Regards

Andy