3 files changed, 7 insertions, 5 deletions
diff --git a/firmware/zpu/lib/hal_io.c b/firmware/zpu/lib/hal_io.c
index 4ed694b9d..d4be324f5 100644
--- a/firmware/zpu/lib/hal_io.c
+++ b/firmware/zpu/lib/hal_io.c
@@ -257,8 +257,9 @@ fngets_noblock(hal_uart_name_t u, char * const s, int len)
 {
   int i;
   for(i=0; i < len; i++) {
-      s[i] = (char) hal_uart_getc_noblock(u);
-      if((s[i] == 255) || (s[i] == '\n')) break;
+      int ret = hal_uart_getc_noblock(u);
+      s[i] = (char) ret;
+      if((ret == -1) || (s[i] == '\n')) break;
   }
   s[i] = 0;
 
diff --git a/firmware/zpu/lib/hal_uart.c b/firmware/zpu/lib/hal_uart.c
index 6a37cceb6..af60bed6a 100644
--- a/firmware/zpu/lib/hal_uart.c
+++ b/firmware/zpu/lib/hal_uart.c
@@ -108,7 +108,7 @@ hal_uart_getc_noblock(hal_uart_name_t u)
 //  int timeout = 0;
 //  while (((uart_regs[u].rxlevel) == 0) && (timeout++ < HAL_UART_TIMEOUT_MS))
 //    mdelay(1);
-  if(uart_regs[u].rxlevel == 0) return 255;
+  if(uart_regs[u].rxlevel == 0) return -1;
   return uart_regs[u].rxchar;
 }
 
diff --git a/firmware/zpu/lib/udp_uart.c b/firmware/zpu/lib/udp_uart.c
index 6f6b9ee91..a3940c05f 100644
--- a/firmware/zpu/lib/udp_uart.c
+++ b/firmware/zpu/lib/udp_uart.c
@@ -94,8 +94,9 @@ void udp_uart_poll(void){
 
         //read all characters we can without blocking
         for (size_t j = state->len; j < sizeof(_states[0].buf); j++){
-            uint8_t ch = hal_uart_getc_noblock((hal_uart_name_t)i);
-            if (ch == 255) break;
+            int ret = hal_uart_getc_noblock((hal_uart_name_t)i);
+            if (ret == -1) break;
+            char ch = (char) ret;
             if (ch == '\n' || ch == '\r') newline = true;
             state->buf[j] = ch;
             state->len++;