From 1b0f79c8186803975540807f1bff726e35167b7c Mon Sep 17 00:00:00 2001
From: Jeremy Soller <jeremy@system76.com>
Date: Fri, 8 Nov 2019 10:29:04 -0700
Subject: [PATCH] Add delay_ticks function

---
 src/arch/8051/delay.c              | 10 +++++++---
 src/arch/8051/include/arch/delay.h |  3 +++
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/src/arch/8051/delay.c b/src/arch/8051/delay.c
index 4f43021..340ad0e 100644
--- a/src/arch/8051/delay.c
+++ b/src/arch/8051/delay.c
@@ -3,6 +3,12 @@
 #include <arch/delay.h>
 #include <arch/timer.h>
 
+void delay_ticks(uint16_t ticks) {
+    timer_mode_1(-ticks);
+    timer_wait();
+    timer_stop();
+}
+
 // One millisecond in ticks is determined as follows:
 //   9.2 MHz is the clock rate
 //   The timer divider is 12
@@ -11,8 +17,6 @@
 //   65536 - 766.667 = 64769.33
 void delay_ms(int ms) {
     for (int i = 0; i < ms; i++) {
-        timer_mode_1(64769);
-        timer_wait();
-        timer_stop();
+        delay_ticks(767);
     }
 }
diff --git a/src/arch/8051/include/arch/delay.h b/src/arch/8051/include/arch/delay.h
index a99e44d..c7393e7 100644
--- a/src/arch/8051/include/arch/delay.h
+++ b/src/arch/8051/include/arch/delay.h
@@ -1,6 +1,9 @@
 #ifndef _ARCH_DELAY_H
 #define _ARCH_DELAY_H
 
+#include <stdint.h>
+
+void delay_ticks(uint16_t ticks);
 void delay_ms(int ms);
 
 #endif // _ARCH_DELAY_H