| ??? 01/30/07 08:05 Read: times |
#131699 - on interfacing both slow and fast on external bus Responding to: ???'s previous message |
Richard Erlacher said:
[...]That would not have to be a concern, though, because the cycle-stretch is controlled internally to the MCU, meaning that a simple change of the SFR will change the cycle length. The requisite external decoding logic will prevent "stepping on" the slower device with a faster cycle. Well, this is one of the options. It sounds to me as laborious as the "manual wiggling of the control pins (whatever the proper term for it might be)", though... Let's conclude, that interfacing a slow device such as 8255 on external bus IS possible in several ways, but not feasible in most modern applications because of a whole range of reasons, among which is the availability of numerous alternative solutions. JW |
