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diff --git a/zap/source/arm/sys/syscall.s b/zap/source/arm/sys/syscall.s
new file mode 100644
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+++ b/zap/source/arm/sys/syscall.s
@@ -0,0 +1,32 @@
+@ Copyright 2022-2023 Gabriel Jensen.
+@ This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
+@ If a copy of the MPL was not distributed with this file, You can obtain one at <https://mozilla.org/MPL/2.0>.
+
+.syntax unified
+
+.arm
+
+.globl zap_syscall
+
+zap_syscall:
+	@ System calls on ARM EABI use the following registers:
+	@ r0 : System call identifier
+	@ r1 : First parameter
+	@ r2 : Second parameter
+	@ r3 : Third parameter
+	@ r4 : Fourth parameter
+	@ r5 : Fifth parameter
+	@ r6 : Sixth parameter
+	@ r0 : Return value
+	push {r4-r5,r7,lr} @ Remember that the parameters are now further up the stack.
+	mov  r7,r0 @ Move the identifier.
+	mov  r0,r1 @ Place parameters.
+	mov  r1,r2
+	mov  r2,r3
+	ldr  r3,[sp,0x10] @ Get the remaining parameters from the stack.
+	ldr  r4,[sp,0x14]
+	ldr  r5,[sp,0x18]
+	svc  0x0 @ Divinity
+	pop  {r4-r5,r7} @ Restore the registers.
+	pop  {r0}
+	bx   r0