diff --git a/compiler/res/prog8lib/cx16/cx16diskio.p8 b/compiler/res/prog8lib/cx16/cx16diskio.p8
index 5e6f749cb..a0bf1f890 100644
--- a/compiler/res/prog8lib/cx16/cx16diskio.p8
+++ b/compiler/res/prog8lib/cx16/cx16diskio.p8
@@ -111,7 +111,7 @@ internal_vload:
             size = 255
             if num_bytes<size
                 size = num_bytes
-            size = cx16.macptr(lsb(size), bufferpointer)
+            size = cx16.macptr(lsb(size), bufferpointer, false)
             if_cs
                 goto byte_read_loop     ; macptr block read not supported, do fallback loop
             diskio.list_blocks += size
diff --git a/compiler/res/prog8lib/cx16/syslib.p8 b/compiler/res/prog8lib/cx16/syslib.p8
index 380c802ea..9ff5b8fb0 100644
--- a/compiler/res/prog8lib/cx16/syslib.p8
+++ b/compiler/res/prog8lib/cx16/syslib.p8
@@ -363,7 +363,7 @@ romsub $fed5 = console_set_paging_message(uword msgptr @R0)  clobbers(A,X,Y)
 romsub $fecf = entropy_get() -> ubyte @A, ubyte @X, ubyte @Y
 romsub $fecc = monitor()  clobbers(A,X,Y)
 
-romsub $ff44 = macptr(ubyte length @A, uword buffer @XY)  clobbers(A) -> ubyte @Pc, uword @XY
+romsub $ff44 = macptr(ubyte length @A, uword buffer @XY, bool dontAdvance @Pc)  clobbers(A) -> bool @Pc, uword @XY
 romsub $ff47 = enter_basic(ubyte cold_or_warm @Pc)  clobbers(A,X,Y)
 romsub $ff4d = clock_set_date_time(uword yearmonth @R0, uword dayhours @R1, uword minsecs @R2, ubyte jiffies @R3)  clobbers(A, X, Y)
 romsub $ff50 = clock_get_date_time()  clobbers(A, X, Y)  -> uword @R0, uword @R1, uword @R2, ubyte @R3   ; result registers see clock_set_date_time()
diff --git a/compiler/src/prog8/compiler/astprocessing/AstChecker.kt b/compiler/src/prog8/compiler/astprocessing/AstChecker.kt
index 0aeb80c5d..f9da5f62b 100644
--- a/compiler/src/prog8/compiler/astprocessing/AstChecker.kt
+++ b/compiler/src/prog8/compiler/astprocessing/AstChecker.kt
@@ -323,8 +323,8 @@ internal class AstChecker(private val program: Program,
                         err("parameter '${param.first.name}' should be (u)word (an address) or str")
                 }
                 else if(param.second.statusflag!=null) {
-                    if (param.first.type != DataType.UBYTE)
-                        err("parameter '${param.first.name}' should be ubyte")
+                    if (param.first.type != DataType.UBYTE && param.first.type != DataType.BOOL)
+                        err("parameter '${param.first.name}' should be bool or ubyte")
                 }
             }
             subroutine.returntypes.zip(subroutine.asmReturnvaluesRegisters).forEachIndexed { index, pair ->
@@ -338,8 +338,8 @@ internal class AstChecker(private val program: Program,
                         err("return type #${index + 1} should be (u)word/address")
                 }
                 else if(pair.second.statusflag!=null) {
-                    if (pair.first != DataType.UBYTE)
-                        err("return type #${index + 1} should be ubyte")
+                    if (pair.first != DataType.UBYTE && pair.first != DataType.BOOL)
+                        err("return type #${index + 1} should be bool or ubyte")
                 }
             }