diff --git a/src/debug/ptyc_dbg_raw.c b/src/debug/ptyc_dbg_raw.c
index 8d30d3e..cd7bb62 100644
--- a/src/debug/ptyc_dbg_raw.c
+++ b/src/debug/ptyc_dbg_raw.c
@@ -52,9 +52,8 @@ int __stdcall ptyc_dbg_raw(struct ptyc_driver_ctx_impl * ictx)
 		for (ch=xch; nbytes; ) {
 			status = ntapi->pty_write(
 				ictx->cctx.hpts,
-				hwait,0,0,
-				&iosb,
-				ch,nbytes,
+				hwait,0,0,&iosb,
+				ch,(uint32_t)nbytes,
 				0,0);
 
 			if (status == NT_STATUS_PENDING)