Enable Arduino interface for Teensy

Author: kklis

ArduinoInterface/readme.txt

@@ -1,4 +1,6 @@
-Additional BDOS calls for Arduino.
+Additional BDOS calls for Arduino / Teensy.
+
+HostOS is available for all platforms - see cpm.h
 
 =====================================================
 
@@ -47,3 +49,12 @@ BDOS function 224 (0xE0) - AnalogWrite:
  LD E, value (0-255)
  CALL 5
 
+=====================================================
+
+BDOS function 250 (0xFA) - HostOS:
+
+ LD C, 250
+ CALL 5
+
+Returns result in HL (1 = Arduino, 4 = Teensy).
+

RunCPM/abstraction_arduino.h

@@ -5,7 +5,11 @@
 #define printf(a, b) Serial.println(b)
 #endif
 
+#ifdef CORE_TEENSY
+#define HostOS 0x04
+#else
 #define HostOS 0x01
+#endif
 
 /* Memory abstraction functions */
 /*===============================================================================*/

RunCPM/cpm.h

@@ -696,7 +696,7 @@ void _Bdos(void) {
 	case 40:
 		HL = _WriteRand(DE);
 		break;
-#ifdef ARDUINO
+#if defined ARDUINO || defined CORE_TEENSY
 		/*
 		C = 220 (DCh) : PinMode
 		*/
@@ -730,7 +730,7 @@ void _Bdos(void) {
 #endif
 		/*
 		C = 250 (FAh) : HostOS
-		Returns: A = 0x00 - Windows / 0x01 - Arduino / 0x02 - Posix / 0x03 - Dos
+		Returns: A = 0x00 - Windows / 0x01 - Arduino / 0x02 - Posix / 0x03 - Dos / 0x04 - Teensy
 		*/
 	case 250:
 		HL = HostOS;