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| -rw-r--r-- | zpu/docs/zpu_arch.html | 28 |
1 files 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 @@ <li> <a href="#memorymap">Memory map</a> <li> <a href="#interrupts">Interrupts</a> <li> <a href="#performance">Speeding up the ZPU</a> +<li> <a href="#debuguart">Debug channel / UART</a> <li> <a href="#wishbone">Wishbone</a> <li> <a href="#zpu_core_small.vhd">About zpu_core_small.vhd</a> <li> <a href="#zpu_core.vhd">About zpu_core.vhd</a> @@ -1040,7 +1041,7 @@ while developing the ZPU. </TD> <TD WIDTH=136> <P LANG="en-US" CLASS="western" ALIGN=CENTER><FONT FACE="Arial, sans-serif"><FONT SIZE=2 STYLE="font-size: 9pt">ZPU - UART to ARM7 TX</FONT></FONT></P> + Debug channel / UART to ARM7 TX</FONT></FONT></P> <P LANG="en-US" CLASS="western" ALIGN=CENTER><FONT FACE="Arial, sans-serif"><FONT SIZE=2 STYLE="font-size: 9pt"><B>NOTE! ZPU side</B></FONT></FONT></P> </TD> @@ -1066,7 +1067,7 @@ while developing the ZPU. </TD> <TD WIDTH=136> <P LANG="en-US" CLASS="western" ALIGN=CENTER><FONT FACE="Arial, sans-serif"><FONT SIZE=2 STYLE="font-size: 9pt">ZPU - UART to ARM7 RX</FONT></FONT></P> + Debug channel / UART to ARM7 RX</FONT></FONT></P> <P LANG="en-US" CLASS="western" ALIGN=CENTER><FONT FACE="Arial, sans-serif"><FONT SIZE=2 STYLE="font-size: 9pt"><B>NOTE! ZPU side</B></FONT></FONT></P> </TD> @@ -1160,7 +1161,7 @@ while developing the ZPU. <P LANG="en-US" CLASS="western"><FONT FACE="Arial, sans-serif"><FONT SIZE=2 STYLE="font-size: 9pt">Bit [31:1] Not used</FONT></FONT></P> <P LANG="en-US" CLASS="western"><FONT FACE="Arial, sans-serif"><FONT SIZE=2 STYLE="font-size: 9pt">Bit - [0] UART RX interrupt enable</FONT></FONT></P> + [0] Debug channel / UART RX interrupt enable</FONT></FONT></P> <P LANG="en-US" CLASS="western"><FONT FACE="Arial, sans-serif"><FONT SIZE=2 STYLE="font-size: 9pt"> 0 Interrupt disable</FONT></FONT></P> <P LANG="en-US" CLASS="western"><FONT FACE="Arial, sans-serif"><FONT SIZE=2 STYLE="font-size: 9pt"> 1 Interrupt @@ -1182,7 +1183,7 @@ while developing the ZPU. <P LANG="en-US" CLASS="western"><FONT FACE="Arial, sans-serif"><FONT SIZE=2 STYLE="font-size: 9pt">Bit [31:1] Not used</FONT></FONT></P> <P LANG="en-US" CLASS="western"><FONT FACE="Arial, sans-serif"><FONT SIZE=2 STYLE="font-size: 9pt">Bit - [0] UART RX interrupt pending (Read)</FONT></FONT></P> + [0] Debug channel / UART RX interrupt pending (Read)</FONT></FONT></P> <P LANG="en-US" CLASS="western"><FONT FACE="Arial, sans-serif"><FONT SIZE=2 STYLE="font-size: 9pt"> 0 No interrupt pending</FONT></FONT></P> <P LANG="en-US" CLASS="western"><FONT FACE="Arial, sans-serif"><FONT SIZE=2 STYLE="font-size: 9pt"> 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. <p> The unique advantages of the ZPU is size in terms of HDL & code size. +<a name="debuguart"/> +<h1>Debug channel / UART</h1> +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. +<p> +The point is that characters(bytes) are sent to/from the ZPU +via some terminal. +<p> +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. +<p> +www.opencores.org has several UART implementations. This is one +of the simpler ones: + +<a href="http://www.opencores.org/projects.cgi/web/uart/overview"> +http://www.opencores.org/projects.cgi/web/uart/overview</a> + <a name="zpu_core.vhd"/> <h1>About zpu_core.vhd</h1> The zpu_core.vhd has a single port memory interface. All data, code and IO is |
