From 0306ce3add02dbe28826f687f86c2c2fae53354c Mon Sep 17 00:00:00 2001
From: Paul Selkirk <paul@psgd.org>
Date: Mon, 2 Nov 2015 18:46:16 -0500
Subject: rewrite and unify uart_send_<numbertype>

---
 src/stm-uart.c | 96 +++++++++++++++++++---------------------------------------
 1 file changed, 31 insertions(+), 65 deletions(-)

(limited to 'src/stm-uart.c')

diff --git a/src/stm-uart.c b/src/stm-uart.c
index 61f3e5b..7676645 100644
--- a/src/stm-uart.c
+++ b/src/stm-uart.c
@@ -41,70 +41,36 @@ void uart_send_string(char *s)
   HAL_UART_Transmit(&huart2, (uint8_t *) s, strlen(s), 0x1);
 }
 
-void uart_send_binary(uint32_t num, uint8_t bits)
+/* Generalized routine to send binary, decimal, and hex integers.
+ * This code is adapted from Chris Giese's printf.c
+ */
+void uart_send_number(uint32_t num, uint8_t digits, uint8_t radix)
 {
-  uint32_t i;
-  uint8_t ch;
-
-  bits--;  /* bits 4 should give i = 1000, not 10000 */
-
-  i = 1 << bits;
-  while (i) {
-    ch = '0';
-    if (num & i) {
-      ch = '1';
-    }
-    uart_send_char(ch);
-    i = i >> 1;
-  }
-}
-
-/* XXX this takes a mask, not a number of digits */
-void uart_send_integer(uint32_t data, uint32_t mag) {
-  uint32_t i, t;
-  uint8_t ch;
-
-  if (! mag) {
-    /* Find magnitude */
-    if (data < 10) {
-      ch = '0' + data;
-      uart_send_char(ch);
-      return;
-    }
-
-    for (mag = 10; mag < data; mag = i) {
-      i = mag * 10;
-      if (i > data || i < mag)
-        break;
-    }
-  }
-  /* mag is now 10 if data is 45, and 1000 if data is 1009 */
-  for (i = mag; i; i /= 10) {
-    t = (data / i);
-    ch = '0' + t;
-    uart_send_char(ch);
-    data -= (t * i);
-  }
-}
-
-void uart_send_hex(uint32_t num, uint8_t digits)
-{
-  uint8_t ch;
-  uint32_t mask;
-
-  mask = 0x0FL << ((digits - 1) * 4);
-
-  if (digits == 0 || digits > 8)
-      digits = 8;
-
-  while (digits) {
-      ch = (num & mask) >> ((digits - 1) * 4);
-      if (ch < 10)
-	  ch += '0';
-      else
-	  ch += 'A' - 10;
-      uart_send_char(ch);
-      --digits;
-      mask >>= 4;
-  }
+    #define BUFSIZE 32
+    char buf[BUFSIZE];
+    char *where = buf + BUFSIZE;
+
+    /* initialize buf so we can add leading 0 by adjusting the pointer */
+    memset(buf, '0', BUFSIZE);
+
+    /* build the string backwards, starting with the least significant digit */
+    do {
+	uint32_t temp;
+	temp = num % radix;
+	where--;
+	if (temp < 10)
+	    *where = temp + '0';
+	else
+	    *where = temp - 10 + 'A';
+	num = num / radix;
+    } while (num != 0);
+
+    if (where > buf + BUFSIZE - digits)
+	/* pad with leading 0 */
+	where = buf + BUFSIZE - digits;
+    else
+	/* number is larger than the specified number of digits */
+	digits = buf + BUFSIZE - where;
+
+    HAL_UART_Transmit(&huart2, (uint8_t *) where, digits, 0x1);
 }
-- 
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