MPC8xx exception handling (or is somebody using 4.5 with MPC8xx)

HongSong Li hsli at
Wed Aug 16 21:56:11 UTC 2000

Check the file "vectors.S" located at
directory for detail. It already includes external interrupt and further CPM
handling routines. But CPM interrupt handler is hard-coded at PPC_IRQ_LVL1
which requires
BSP to conform with it(see comments in source code). All the codes will be
linked to .vectors
section which defined in "link_cmds" file so as to catch up exceptions.

----- Original Message -----
From: "Peer Stritzinger" <pstrtems at>
To: "RTEMS Users" <rtems-users at>
Sent: Wednesday, August 16, 2000 5:17 PM
Subject: MPC8xx exception handling (or is somebody using 4.5 with MPC8xx)

> Hi,
> I'm trying to build a BSP for a MPC850 board using the bare BSP
> (MPC860) using RTEMS 4.5.0beta3.
> At the moment I have troubles getting the exception handling to run
> for the on chip ``external'' interrupts.
> In the file:
> there is support for the on chip interrupt handler irq's that are
> routed to the external interrupt (at 0x500).  For example when I want
> to have a handler for the LVL1 irq I can install it at vector
> PPC_IRQ_LVL1.  This installs a pseudo irq stub but this stub is never
> called because there is no generic external interrupt handler (that
> should be installed at 0x500) to reroute the irq to the pseudo stub.
> Did I miss something?
> Is anybody using 4.5 with MPC8xx?
> If yes how are is the on chip interrupt handler used?
> Peer Stritzinger

More information about the users mailing list