diff --git a/seminaries/qtmips/call-syscall/lec10-01-call4-clobber.S b/seminaries/qtmips/call-syscall/lec10-01-call4-clobber.S
new file mode 100644
index 0000000000000000000000000000000000000000..b005ff0a2e2b841376f73a229927353fb135acd0
--- /dev/null
+++ b/seminaries/qtmips/call-syscall/lec10-01-call4-clobber.S
@@ -0,0 +1,39 @@
+// select core without pipeline but with delay slot
+
+#pragma qtmips show registers
+#pragma qtmips show memory
+#pragma qtmips show peripherals
+
+.equ SPILED_REG_LED_LINE, 0xffffc104 // 32 bit word mapped as output
+.equ STACK_INIT, 0x01230000 // The bottom of the stack, the stack grows down
+
+.set noreorder
+.text
+
+main:
+ la $sp, STACK_INIT
+ li $s0, 0x12345678
+ addi $a0, $0, 2
+ addi $a1, $0, 3
+ addi $a2, $0, 4
+ addi $a3, $0, 5
+ jal fun
+ nop
+ add $t0, $v0, $0
+ sw $t0, SPILED_REG_LED_LINE($0)
+final:
+ break
+ beq $0, $0, final
+
+// int fun(int g, h, i, j)
+// g→$a0, h→$a1, i→$a2, j→$a3, $v0 – ret. val, $sX – save, $tX – temp, $ra – ret. addr
+// return (g + h) – (i + j)
+fun:
+ add $t0, $a0, $a1
+ add $t1, $a2, $a3
+ sub $s0, $t0, $t1
+ add $v0, $s0, $0
+ jr $ra
+ nop
+
+#pragma qtmips focus memory STACK_INIT-4*8
diff --git a/seminaries/qtmips/call-syscall/lec10-02-call4-save.S b/seminaries/qtmips/call-syscall/lec10-02-call4-save.S
new file mode 100644
index 0000000000000000000000000000000000000000..f65861eab1ff6dd58ff1e9ab6dfad3fd74a963ea
--- /dev/null
+++ b/seminaries/qtmips/call-syscall/lec10-02-call4-save.S
@@ -0,0 +1,43 @@
+// select core without pipeline but with delay slot
+
+#pragma qtmips show registers
+#pragma qtmips show memory
+#pragma qtmips show peripherals
+
+.equ SPILED_REG_LED_LINE, 0xffffc104 // 32 bit word mapped as output
+.equ STACK_INIT, 0x01230000 // The bottom of the stack, the stack grows down
+
+.set noreorder
+.text
+
+main:
+ la $sp, STACK_INIT
+ li $s0, 0x12345678
+ addi $a0, $0, 2
+ addi $a1, $0, 3
+ addi $a2, $0, 4
+ addi $a3, $0, 5
+ jal fun
+ nop
+ add $t0, $v0, $0
+ sw $t0, SPILED_REG_LED_LINE($0)
+final:
+ break
+ beq $0, $0, final
+
+// int fun(int g, h, i, j)
+// g→$a0, h→$a1, i→$a2, j→$a3, $v0 – ret. val, $sX – save, $tX – temp, $ra – ret. addr
+// return (g + h) – (i + j)
+fun:
+ addi $sp, $sp, -4
+ sw $s0, 0($sp) // Save $s0 on stack
+ add $t0, $a0, $a1
+ add $t1, $a2, $a3 // Procedure body
+ sub $s0, $t0, $t1
+ add $v0, $s0, $zero // Result
+ lw $s0, 0($sp) // Restore $s0
+ addi $sp, $sp, 4
+ jr $ra // Return
+ nop
+
+#pragma qtmips focus memory STACK_INIT-4*8
diff --git a/seminaries/qtmips/call-syscall/lec10-03-fact-buggy.S b/seminaries/qtmips/call-syscall/lec10-03-fact-buggy.S
new file mode 100644
index 0000000000000000000000000000000000000000..6476fdde156ebc48b59f3a7bebaaeb067747fb7a
--- /dev/null
+++ b/seminaries/qtmips/call-syscall/lec10-03-fact-buggy.S
@@ -0,0 +1,43 @@
+// select core without pipeline but with delay slot
+
+#pragma qtmips show registers
+#pragma qtmips show memory
+#pragma qtmips show peripherals
+
+.equ SPILED_REG_LED_LINE, 0xffffc104 // 32 bit word mapped as output
+.equ STACK_INIT, 0x01230000 // The bottom of the stack, the stack grows down
+
+.set noreorder
+.text
+
+main:
+ la $sp, STACK_INIT
+ addi $a0, $0, 4 // 4! -> 24
+ jal fact
+ nop
+ add $s0, $v0, $0
+ sw $s0, SPILED_REG_LED_LINE($0)
+final:
+ break
+ beq $0, $0, final
+ nop
+
+fact:
+ addi $sp, $sp, -4 // adjust stack for 2 items
+ sw $a0, 0($sp) // save argument
+ slti $t0, $a0, 1 // test for n < 1
+ beq $t0, $zero, L1
+ addi $v0, $zero, 1 // if so, result is 1
+ addi $sp, $sp, 4 // pop 2 items from stack
+ jr $ra // and return
+ nop
+L1: addi $a0, $a0, -1 // else decrement n
+ jal fact // recursive call
+ nop
+ lw $a0, 0($sp) // restore original n
+ addi $sp, $sp, 4 // pop 2 items from stack
+ mul $v0, $a0, $v0 // multiply to get result
+ jr $ra // and return
+ nop
+
+#pragma qtmips focus memory STACK_INIT-4*8
diff --git a/seminaries/qtmips/call-syscall/lec10-04-fact-ok.S b/seminaries/qtmips/call-syscall/lec10-04-fact-ok.S
new file mode 100644
index 0000000000000000000000000000000000000000..6c3e8dc32c5042fc87ff7460ac82b7d8249ab5ac
--- /dev/null
+++ b/seminaries/qtmips/call-syscall/lec10-04-fact-ok.S
@@ -0,0 +1,45 @@
+// select core without pipeline but with delay slot
+
+#pragma qtmips show registers
+#pragma qtmips show memory
+#pragma qtmips show peripherals
+
+.equ SPILED_REG_LED_LINE, 0xffffc104 // 32 bit word mapped as output
+.equ STACK_INIT, 0x01230000 // The bottom of the stack, the stack grows down
+
+.set noreorder
+.text
+
+main:
+ la $sp, STACK_INIT
+ addi $a0, $0, 4 // 4! -> 24
+ jal fact
+ nop
+ add $s0, $v0, $0
+ sw $s0, SPILED_REG_LED_LINE($0)
+final:
+ break
+ beq $0, $0, final
+ nop
+
+fact:
+ addi $sp, $sp, -8 // adjust stack for 2 items
+ sw $ra, 4($sp) // save return address
+ sw $a0, 0($sp) // save argument
+ slti $t0, $a0, 1 // test for n < 1
+ beq $t0, $zero, L1
+ addi $v0, $zero, 1 // if so, result is 1
+ addi $sp, $sp, 8 // pop 2 items from stack
+ jr $ra // and return
+ nop
+L1: addi $a0, $a0, -1 // else decrement n
+ jal fact // recursive call
+ nop
+ lw $a0, 0($sp) // restore original n
+ lw $ra, 4($sp) // and return address
+ addi $sp, $sp, 8 // pop 2 items from stack
+ mul $v0, $a0, $v0 // multiply to get result
+ jr $ra // and return
+ nop
+
+#pragma qtmips focus memory STACK_INIT-4*8
diff --git a/seminaries/qtmips/call-syscall/lec10-05-call-6args.S b/seminaries/qtmips/call-syscall/lec10-05-call-6args.S
new file mode 100644
index 0000000000000000000000000000000000000000..6c3e8dc32c5042fc87ff7460ac82b7d8249ab5ac
--- /dev/null
+++ b/seminaries/qtmips/call-syscall/lec10-05-call-6args.S
@@ -0,0 +1,45 @@
+// select core without pipeline but with delay slot
+
+#pragma qtmips show registers
+#pragma qtmips show memory
+#pragma qtmips show peripherals
+
+.equ SPILED_REG_LED_LINE, 0xffffc104 // 32 bit word mapped as output
+.equ STACK_INIT, 0x01230000 // The bottom of the stack, the stack grows down
+
+.set noreorder
+.text
+
+main:
+ la $sp, STACK_INIT
+ addi $a0, $0, 4 // 4! -> 24
+ jal fact
+ nop
+ add $s0, $v0, $0
+ sw $s0, SPILED_REG_LED_LINE($0)
+final:
+ break
+ beq $0, $0, final
+ nop
+
+fact:
+ addi $sp, $sp, -8 // adjust stack for 2 items
+ sw $ra, 4($sp) // save return address
+ sw $a0, 0($sp) // save argument
+ slti $t0, $a0, 1 // test for n < 1
+ beq $t0, $zero, L1
+ addi $v0, $zero, 1 // if so, result is 1
+ addi $sp, $sp, 8 // pop 2 items from stack
+ jr $ra // and return
+ nop
+L1: addi $a0, $a0, -1 // else decrement n
+ jal fact // recursive call
+ nop
+ lw $a0, 0($sp) // restore original n
+ lw $ra, 4($sp) // and return address
+ addi $sp, $sp, 8 // pop 2 items from stack
+ mul $v0, $a0, $v0 // multiply to get result
+ jr $ra // and return
+ nop
+
+#pragma qtmips focus memory STACK_INIT-4*8
diff --git a/seminaries/qtmips/call-syscall/lec10-06-linus-hello.S b/seminaries/qtmips/call-syscall/lec10-06-linus-hello.S
new file mode 100644
index 0000000000000000000000000000000000000000..083a71bf6af00df11b030fa70add9b9c314f1d09
--- /dev/null
+++ b/seminaries/qtmips/call-syscall/lec10-06-linus-hello.S
@@ -0,0 +1,63 @@
+// The first program run by Linus on MIPS Linux kernel port
+
+
+// select core without pipeline but with delay slot
+
+#pragma qtmips show registers
+#pragma qtmips show memory
+#pragma qtmips show terminal
+
+// #include <asm/unistd.h>
+// #include <asm/asm.h>
+// #include <sys/syscall.h>
+
+.equ O_RDWR, 02
+
+// Linux kernel compatible system calls subset
+
+.equ SYS_exit, 4001 // void exit(int status)
+.equ SYS_read, 4003 // ssize_t read(int fd, void *buf, size_t count)
+.equ SYS_write, 4004 // ssize_t write(int fd, const void *buf, size_t count)
+.equ SYS_close, 4006 // int close(int fd)
+.equ SYS_open, 4005 // int open(const char *pathname, int flags, mode_t mode)
+.equ SYS_brk, 4045 // void * brk(void *addr)
+.equ SYS_truncate, 4092 // int ftruncate(int fd, off_t length)
+.equ SYS_readv, 4145 // ssize_t readv(int fd, const struct iovec *iov, int iovcnt)
+.equ SYS_writev, 4146 // ssize_t writev(int fd, const struct iovec *iov, int iovcnt)
+
+.set noreorder
+.text
+
+// LEAF(main)
+// fd = open("/dev/tty1", O_RDWR, 0);
+ la $a0, tty
+ li $a1, O_RDWR
+ li $a2, 0
+ li $v0, SYS_open
+ syscall
+ bne $a3, $0, quit
+ addi $s0, $v0, 0 // delay slot
+// write(fd, "hello, world.\n", 14);
+ addi $a0, $s0, 0
+ la $a1, hello
+ li $a2, 14
+ li $v0, SYS_write
+ syscall
+// close(fd);
+ addi $a0, $s0, 0
+ li $v0, SYS_close
+ syscall
+
+quit:
+ li $a0, 0
+ li $v0, SYS_exit
+ syscall
+
+ j quit
+ nop
+
+// END(main)
+
+ .data
+tty: .asciz "/dev/tty1"
+hello: .ascii "Hello, world.\n"