operating system - what is the difference between memory mapped io and io mapped io -

-

pls explain difference between memory mapped io , io mapped io

on x86 there 2 different address spaces, 1 memory, , 1 i/o ports.

the port address space limited 65536 ports, , accessed using in/out instructions.

as example, video card's vga functionality can accessed using i/o ports, framebuffer memory-mapped.

other cpu architectures have 1 address space. in architectures, devices memory-mapped.


Comments

Post a Comment

Popular posts from this blog

silverlight - Applying a style to ItemContainerStyle in C# -

-
when i'm applying style listbox.itemcontainerstyle in c# isn't making change @ runtime. i'm using; mylistbox.itemcontainerstyle = (style)(app.current.resources["newitemstyle"]); however other styles being supplied, such buttons etc i'm going mybutton.style = (style)(app.current.resources["mymainbuttonstyle"]); i don't errors either, nothing , reverts default system style. i using app.current.resources instead of resources because "newitemstyle" wasn't defined in whole application. mistake.
Read more

c# - NullReferenceException in MySqlClient.NativeDriver -

-
i have long running program exectues mysql-queries every 5 minutes (timed thread). after has run approximately 10 hours nullreferenceexception thrown following stacktrace: at mysql.data.mysqlclient.nativedriver.getresult(int32& affectedrow, int32& insertedid) bei mysql.data.mysqlclient.driver.getresult(int32 statementid, int32& affectedrows, int32& insertedid) @ mysql.data.mysqlclient.driver.nextresult(int32 statementid) @ mysql.data.mysqlclient.mysqldatareader.nextresult() @ mysql.data.mysqlclient.mysqldatareader.close() @ mysql.data.mysqlclient.mysqlcommand.resetreader() @ mysql.data.mysqlclient.mysqlcommand.executereader(commandbehavior behavior) @ mysql.data.mysqlclient.mysqlcommand.executenonquery() @ myownprogram.mysql.senddata(string sqlcommmand) the senddata method following (lockdb of type object) public void senddata(string sqlcommmand) { try { using(mysqlcommand command = connection.createcommand()...
Read more

php - How can I merge Nodes & Webform Submissions into instances of one general Content Type in Drupal 6? -

-
i built site using drupal 6 allows users submit information site owner in 3 different ways. are: webform a : quick contact - collects name, email, phone , message. webform b : free pdf book email webform - collects info similar above, , sends user email pdf attachment book written site owner. node create : case evaluation - form node creation page using multi-step module, cck , lot of conditional fields. anonymous users can fill out form , node data emailed site owner based on rule created. all 3 of these forms work in terms of doing supposed site. webform submissions accessed webform node owner, , set table view manage node submissions. even though forms gathering different data, @ end of day, important data personal contact information (each 1 collects name, email and/or phone), , each form submission (from of forms) considered lead owner , followed on. i centralize these various form submissions (2 webforms + 1 node) 1 content type (leads) managed 1 page, rather t...
Read more