diff --git a/fpga/zsbl/bios.S b/fpga/zsbl/bios.S
deleted file mode 100644
index a7283b38d..000000000
--- a/fpga/zsbl/bios.S
+++ /dev/null
@@ -1,102 +0,0 @@
-#include "system.h"
-
-PERIOD = (SYSTEMCLOCK / 2)
-
-.section .init
-.global _start
-.type _start, @function
-
-		
-_start:
-	  # Initialize global pointer
-	.option push
-	.option norelax
-	1:auipc gp, %pcrel_hi(__global_pointer$)
-	addi  gp, gp, %pcrel_lo(1b)
-	.option pop
-	
-	li x1, 0
-	li x2, 0
-	li x4, 0
-	li x5, 0
-	li x6, 0
-	li x7, 0
-	li x8, 0
-	li x9, 0
-	li x10, 0
-	li x11, 0
-	li x12, 0
-	li x13, 0
-	li x14, 0
-	li x15, 0
-	li x16, 0
-	li x17, 0
-	li x18, 0
-	li x19, 0
-	li x20, 0
-	li x21, 0
-	li x22, 0
-	li x23, 0
-	li x24, 0
-	li x25, 0
-	li x26, 0
-	li x27, 0
-	li x28, 0
-	li x29, 0
-	li x30, 0
-	li x31, 0
-
-
-	# set the stack pointer to the top of memory - 8 bytes (pointer size)
-	li sp, (EXT_MEM_END - 8)
-
-	li a0, 0x00000000
-	li a1, EXT_MEM_BASE
-	#li a2, 128*1024*1024/512 # copy 128MB
-	li a2, 127*1024*1024/512 # copy 127MB upper 1MB contains the return address (ra)
-	#li a2, 800 # copy 400KB
-	jal ra, copyFlash
-	
-	fence.i
-	# now toggle led so we know the copy completed.
-
-	# write to gpio
-	li	t2, 0xFF
-	la	t3, 0x1006000C
-	li	t4, 5
-
-loop:
-
-	# delay
-	li	t0, PERIOD/2
-delay1:	
-	addi	t0, t0, -1
-	bge	t0, x0, delay1
-	sw	t2, 0x0(t3)
-
-	li	t0, PERIOD/2
-delay2:	
-	addi	t0, t0, -1
-	bge	t0, x0, delay2
-	sw	x0, 0x0(t3)
-
-	addi	t4, t4, -1
-	bgt	t4, x0, loop
-
-
-	# now that the card is copied and the led toggled we
-	# jump to the copied contents of the sd card.
-
-jumpToLinux:	
-	csrrs	a0, 0xF14, x0   # copy hart ID to a0
-	li	a1, FDT_ADDRESS  # This is the device tree address
-	la	a2, end_of_bios
-	li	t0, EXT_MEM_BASE  # start of code
-	
-	jalr	x0, t0, 0
-
-end_of_bios:	
-
-	
-
-