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Is it possible to simulate the 8255 by a plugin or anything else in keil µvision 2 ?
Greetings
Martin
The 8255 dates back to the late 70's and is obsolete for any use and has been obsolete for '51 use for a longer time.
Up till a few years ago many lazy instrctors had not removed the antique from their course material (it is work to make new course material) and the various fora were flooded by questions about it. 'Graduates' from those schools were chastised for using the antique in real life projects. As a result I believe it has been 2 years since the 8255 last appeared at 8052.com/keil.com./cygnsl.com/NXP.com.
Whatever you have to learn to make the 8255 work will teach you wrong approaches since the 8255 is designed for the x86 chips and the hoops to jump through to to use it only apply when attempting to interface something with an x86 concept to a '51 which nobody needs to now that there is legio chips matching the '51 bus.
20 years ago (a millenium in electronics) the 8255 was the chip of choice (you had no other choice) about then compunents fitting the '51 bus started to come out and anyone with any sense/knowledge sold their 8255s to an antique shop.
you can refer to www.8052.com/.../119914 www.8052.com/.../119927 www.8052.com/.../119928
Anyhow if you attend a school that still teaches the 8255 as the holy grail IMMEDIATELY go request you money back.
Erik
"Whatever you have to learn to make the 8255 work will teach you wrong approaches"
As an exercise in interfacing, it is a perfectly valid exercise.
As an example of current practice, it isn't.
As an exercise in interfacing, it is a perfectly valid exercise. As an example of current practice, it isn't. making a device made for MMIO work with port I/O because it is too slow for MMIO with todays practice, or run a 12 clock '51 with a 4 MHz crystal and do MMIO.
To the OP: the main validity in an exercise with a 8255 is to teach you to check timing of all devices in the datasheets, putting a modern '51 and a 8255 together 'naturally' WILL fail.
Ok. This school doesn´t teach the 8255 as "the Holy Grail"
I think it´s an exercise just to think about 8051 and peripherie.
Greetings from Germany
Why are we to work with this antique? are you just too lazy to upgrade the curriculum?
make your instructor aware of this thread