From: R. Steve McKown <rsmckown@gmail.com>
Date: Thu, 8 Apr 2010 00:46:48 +0000 (-0600)
Subject: Some comments about the UART ISRs.
X-Git-Tag: debian/2.1.0-4-1tmi~1^2~6
X-Git-Url: https://oss.titaniummirror.com/gitweb/?p=tinyos-2.x.git;a=commitdiff_plain;h=704e3e7ba90d136a08eb9ed930bf3552b5540517

Some comments about the UART ISRs.
---

diff --git a/tos/chips/msp430/usci/Msp430UartP.nc b/tos/chips/msp430/usci/Msp430UartP.nc
index 742c1674..6f6384db 100644
--- a/tos/chips/msp430/usci/Msp430UartP.nc
+++ b/tos/chips/msp430/usci/Msp430UartP.nc
@@ -163,6 +163,9 @@ implementation {
 
   async event void Interrupts.tx()
   {
+    /* FIXME: this can cause an arbitrarily long ISR, if m_slen is large.
+     * But depending on timing, we may always only write 1 byte.
+     */
     while (m_slen && call Registers.getIfgTx()) {
       call Registers.setTxbuf(*m_sbuf);
       if (--m_slen)
@@ -238,6 +241,9 @@ implementation {
   {
     if (m_robuf) {
       /* receive() takes precedence if active */
+      /* FIXME: an arbitrarily long ISR may occur if m_rlen is large.
+       * But depending on timing, we may always only read 1 byte.
+       */
       while (m_rlen && call Registers.getIfgRx()) {
 	*m_rbuf = byte;
 	if (--m_rlen)