Comments?

-- 
Øyvind Harboe
US toll free 1-866-980-3434 / International +47 51 63 25 00
http://www.zylin.com/zy1000.html
ARM7 ARM9 ARM11 XScale Cortex
JTAG debugger and flash programmer
From 3a3ab896c350ff5a177837561b3042c12e3fc7c3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=98yvind=20Harboe?= <[email protected]>
Date: Sat, 7 Aug 2010 22:07:56 +0200
Subject: [PATCH] lpc1768: slower safer default settings
MIME-Version: 1.0
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srst does not pull trst on the lpc1768 I tried(Keil PCB),
reset halt works fine.

reduce default frequency to 100kHz and leave comment that
a decent PCB specific script should increase the chip
frequency in reset-init

Signed-off-by: Øyvind Harboe <[email protected]>
---
 tcl/target/lpc1768.cfg |   13 ++++++++-----
 1 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/tcl/target/lpc1768.cfg b/tcl/target/lpc1768.cfg
index ff92e4a..cd67b14 100644
--- a/tcl/target/lpc1768.cfg
+++ b/tcl/target/lpc1768.cfg
@@ -28,8 +28,7 @@ if { [info exists CPUTAPID ] } {
 adapter_nsrst_delay 200
 jtag_ntrst_delay 200
 
-# LPC2000 & LPC1700 -> SRST causes TRST
-reset_config srst_pulls_trst
+reset_config trst_and_srst srst_nogate
 
 jtag newtap $_CHIPNAME cpu -irlen 4 -expected-id $_CPUTAPID
 
@@ -54,9 +53,13 @@ flash bank $_FLASHNAME lpc2000 0x0 0x80000 0 0 $_TARGETNAME \
 # Although rclk "appears to work", it turns out that this yields
 # 4MHz whereas the "correct" rate is CCLK/6, which is not what
 # you get with rclk.
-jtag_khz [ expr 4000 / 6 ]
-
-
+#
+# Experimentation shows that we have to use as low as 100kHz for
+# 4MHz parts to ensure that reset works properly. A decent 
+# PCB specific configuration file should increase the JTAG clock
+# rate during reset-init after having switched from RC oscilator
+# to a faster clock.
+jtag_khz 100
 
 $_TARGETNAME configure -event reset-init {
 	# Do not remap 0x0000-0x0020 to anything but the flash (i.e. select
-- 
1.7.0.4

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