FSBUS A/D problem

[Guest Dylan]

Hi all,I'm a FSBUS user in my 737 home cockpit, i have 3 key cards, 2 led cards, 1 A/D card and 12 display cards. It happens SOMETIMES that with a key pression i get also one or more key pressed from the same key card.Exemple. I push the HDG button and i get HDG, and another or more keys pressed.I finally found the problem but i can't fix it: everything works ok if i don't connect the A/D card.When i connect it, i get the interferences in the key cards.The key cards have CID 1,2 and 3 and i tried to change the A/D card CID from 4 to 7 but the problem remains.I just checked in FSBUS A/D card documentation and found to use only PIC 16F84 A type in A/D cards while i'm using a normal PIC 16F84 not A type.Could this be the problem?I just would like to know before order the A type.Should i try to change the quartz?Any idea?Thanks in advanceDylan

[Guest Erups]

The 16f84 and 16f84a are totally compatible, microchip says.I believe it's something software related, have you asked Dirk?

[Guest Dylan]

Ciao Claudio, i'm italian too, and thanks for reply,my question is because in the A/D card electrical scheme, and ONLY in it, there is written "use 16F84 A-Type only!" and not in other FSBUS cards.Tomorrow i'll try to change the quartz but it's really so strange.I asked Dirk too but i'm still waiting for an answer.thanks againDylan (Fabrizio)

[Guest Erups]

>my question is because in the A/D card electrical scheme, and>ONLY in it, there is written "use 16F84 A-Type only!" and not>in other FSBUS cards.Then i guess Dirk used that insignificant little bit of difference that microchip put in the 84A to the fullest.Thus makeing the 84 not compatible.