RE: userport: C64, Plus4, others?

Hallo Gábor, 


Jim > You do need to ensure 2 more lines besides the 8 data lines....

One of my very first projects was the ancestor of CBM-HD: the Userport was connected to the LPT port of a PC. In this case I only used 4 bits for data transfer (the same four bits as used by X1541) plus two data bits and two bits of the status port for handshake. Not the fastest way but the most surest: I had control of every bit of both systems.

Then I turned the LPT port into a bidirectional, used DATA and CLOCK of the IEC bus as handshake lines and PA2 to tell the PC whether the these last two lines were valid or not. In this case I knew that if there was an error, I only had to look in the communication part as the rest proofed to work fine with the 4-bit solution. Again, not the ideal way but I learned a lot again and it was fun!

I hope this helps a bit.


--
     ___
    / __|__
   / /  |_/     Groetjes, Ruud
   \ \__|_\
    \___|       URL: Ruud.C64.org


 
De informatie in dit e-mailbericht is vertrouwelijk en uitsluitend bestemd voor de 
geadresseerde. Wanneer u dit bericht per abuis ontvangt, verzoeken wij u contact op te 
nemen met de afzender per kerende e-mail. Verder verzoeken wij u in dat geval dit 
e-mailbericht te vernietigen en de inhoud ervan aan niemand openbaar te maken. 
Wij aanvaarden geen aansprakelijkheid voor onjuiste, onvolledige dan wel ontijdige 
overbrenging van de inhoud van een verzonden e-mailbericht, noch voor daarbij 
overgebrachte virussen.

APG Algemene Pensioen Groep NV is gevestigd te Heerlen en is ingeschreven in het 
handelsregister van de Kamer van Koophandel Limburg onder nummer 14099617


The information contained in this e-mail is confidential and may be privileged. 
It may be read, copied and used only by the intended recipient. 
If you have received it in error, please contact the sender immediately by 
return e-mail; please delete in this case the e-mail and do not disclose it's 
contents to any person. We don't accept liability for any errors, omissions, 
delays of receipt or viruses in the contents of this message which arise as a 
result of e-mail transmission.

APG Algemene Pensioen Groep NV is registered in the trade register of the Chamber 
of Commerce Limburg, The Netherlands, registration number: 14099617


       Message was sent through the cbm-hackers mailing list