> Hi, I am investigating the possibillity to have 4 PIC 16F877 connected
> to the same PC on a RS232 'bus'.
> I am using MAX220CPE, can they be connected in parallell or will they go
> up in flames ?

The only 'official' way to do this (assuming you want the PC to talk to the
PICs and the PICs to the PC, not PICs to PICs) is to daisy chain the
devices: Downstreams from the PC each devices converts the V24 to TTL (to
feed the PIC) and the TTL back to V24 (to feed the next device). Upstreams
each device converst what it receives from the previous device to TTL, adds
(or substracts, check the polarity) its own signal, and converts it to V24
again for the next device or the PC. When I have the time I'll modify
WISP/Wbus to use this principle, seem the current Wisp/Wbus for a cheaper
but much less reliable way to chain V24 devices.

Wouter

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