This serial comm. card made in 1987(?) is much smaller than the MCA card made in 1991.
Why? The same thing is with MCA ethernet cards. Why were they designed so big?
Because MCA is 32-bit and intelligent. It needs some more chips than a dumb 8-bit ISA card.
Also, it was probably recommended by IBM to make MCA cards full-length.
Isn't this a 16 bit card? The 32 bit MCA bus looks different.
wrote:Isn't this a 16 bit card? The 32 bit MCA bus looks different.
Yes, 16-bit.
But that ISA card is 8-bit.
So, in order to interface 8-bit stuff to 16-bit bus, some additional logic is necessary.
And then some more to support automatic configuration.
Edit:
But not all MCA cards have to be more complicated than ISA ones, see eg. those 3Com EtherLink III NICs - the main chip contains all the logic necessary to interface with MCA, thus keeping the card about as simple as the ISA one...
Nie tylko, jak widzicie, w tym trudność, że nie zdołacie wejść na moją górę, lecz i w tym, że ja do was cały zejść nie mogę, gdyż schodząc, gubię po drodze to, co miałem donieść.
It looks like the MCA card has enough chips to provide dual serial ports, yet there are no extra headers as far as I can tell. That thing is huge for what it does. The 16 bit ISA serial cards are nowhere near that size. Are you certain that this card is actually a serial controller?
"Will the highways on the internets become more few?" -Gee Dubya
V'Ger XT|Upgraded AT|Ultimate 386|Super VL/EISA 486|SMP VL/EISA Pentium
wrote:Are you certain that this card is actually a serial controller?
Certain? Never. I'm not familiar with these buses at all and only started reading about them recently. This card has a 25 pin RS-232 connector, it's advertised as a RS-232 multiprotocol adapter and from what I read they were used for external modem connections.
There are shorter cards like Grzyb mentioned but many of them are full length for some reason.
One would think manufacturers wanted smaller cards to reduce costs but not IBM.
It's a little funny seeing full-length cards in a 486 system in 1992 when most 16 bit ISA systems had half-length or smaller cards at the same time. Even the 32 bit VLB is shorter.
That card looks like IBM 90x8460 Multi-Protocol Adapter Card, so probably does stuff like SDLC/HDLC...
Nie tylko, jak widzicie, w tym trudność, że nie zdołacie wejść na moją górę, lecz i w tym, że ja do was cały zejść nie mogę, gdyż schodząc, gubię po drodze to, co miałem donieść.
