From 6f3db230ca9d2e32df61dbd6137ea963de630629 Mon Sep 17 00:00:00 2001 From: oharboe Date: Fri, 22 Aug 2008 13:15:21 +0000 Subject: added uart section --- zpu/docs/zpu_arch.html | 28 ++++++++++++++++++++++++---- 1 file changed, 24 insertions(+), 4 deletions(-) diff --git a/zpu/docs/zpu_arch.html b/zpu/docs/zpu_arch.html index 280cda3..5d7fc5e 100644 --- a/zpu/docs/zpu_arch.html +++ b/zpu/docs/zpu_arch.html @@ -12,6 +12,7 @@
  • Memory map
  • Interrupts
  • Speeding up the ZPU +
  • Debug channel / UART
  • Wishbone
  • About zpu_core_small.vhd
  • About zpu_core.vhd @@ -1040,7 +1041,7 @@ while developing the ZPU.

    ZPU - UART to ARM7 TX

    + Debug channel / UART to ARM7 TX

    NOTE! ZPU side

    @@ -1066,7 +1067,7 @@ while developing the ZPU.

    ZPU - UART to ARM7 RX

    + Debug channel / UART to ARM7 RX

    NOTE! ZPU side

    @@ -1160,7 +1161,7 @@ while developing the ZPU.

    Bit [31:1] Not used

    Bit - [0] UART RX interrupt enable

    + [0] Debug channel / UART RX interrupt enable

    0 Interrupt disable

    1 Interrupt @@ -1182,7 +1183,7 @@ while developing the ZPU.

    Bit [31:1] Not used

    Bit - [0] UART RX interrupt pending (Read)

    + [0] Debug channel / UART RX interrupt pending (Read)

    0 No interrupt pending

    1 Interrupt @@ -1455,6 +1456,25 @@ Achieving above 50-100 DMIPS with the current ZPU architecture is probably a non-starter and a more conventional RISC design makes more sense here.

    The unique advantages of the ZPU is size in terms of HDL & code size. + +

    Debug channel / UART

    +All self respecting embedded projects should have a debug channel +to print stuff to. Typically this is a standard RS232 or UART, but +it can also be something more exotic like a DCC JTAG channel. +

    +The point is that characters(bytes) are sent to/from the ZPU +via some terminal. +

    +The ZPU defines in the memory map a UART / debug channel. This +should be implemented by some suitable debug channel for +the device in which the ZPU is implemented. +

    +www.opencores.org has several UART implementations. This is one +of the simpler ones: + + +http://www.opencores.org/projects.cgi/web/uart/overview +

    About zpu_core.vhd

    The zpu_core.vhd has a single port memory interface. All data, code and IO is -- cgit v1.1