* Document ztdummy changes.

* It's a (ztdummy) clock source, not ztdummy type.


git-svn-id: http://svn.digium.com/svn/zaptel/branches/1.4@3044 5390a7c7-147a-4af0-8ec9-7488f05a26cb

1 files changed, 11 insertions, 2 deletions

diff --git a/README b/README
index dfff136..b33f7c1 100644
--- a/README
+++ b/README
@@ -97,8 +97,11 @@ If you build a custom kernel, note the following configuration items:
   be selected These can be selected from the "Library Routines" submenu 
   during kernel configuration via "make menuconfig".
 - If you don't have any zaptel hardware, you need ztdummy.
-  * ztdummy on i386/amd64 and later kernels (>= 2.6.15) can (and should)
-    use the system's RTC (Real Time Clock).
+  * ztdummy on i386/x86_64 with kernels >= 2.6.22 can (and should) use 
+    high resolution times (CONFIG_HIGH_RES_TIMERS), and (if available, 
+    the system HPET.
+  * ztdummy on i386/x86_64 and later kernels (>= 2.6.15) can use the 
+    system's RTC (Real Time Clock).
   * Alternatives to that for ztdummy are a UHCI USB controller (USB
     controllers made by Intel or VIA) or a kernel that has HZ=1000
     (default on kernels 2.6.0-2.6.12, optional on newer kernels. Not
@@ -333,6 +336,12 @@ first cycle. Eitherwise it will just give you in each cycle the percent
 of how close it was. Also try running it with the option -v for a
 verbose output.
 
+To check the clock source that is built into ztdummy, you can either
+look at title of its span in /proc/zaptel file for a "source:" in the
+description. Or even run:
+
+  strings zaptel.ko | grep source:
+
 
 Spans and Channels
 ------------------