user: Demonstrate the C code that generates the assembly output below:

```asm
<main>:
  endbr64
  push   %r12
  push   %rbp
  push   %rbx
  lea    D21(%rip),%rbx
  nop
L8:
  mov    %rbx,%rdi
  call   <puts@plt>
  xor    %eax,%eax
  call   <getchar@plt>
  mov    %rax,%rbp
  xor    %eax,%eax
  call   <getchar@plt>
  sub    $0x30,%ebp
  cmp    $0x1,%ebp
  ja     L8
  lea    D46(%rip),%rdi
  lea    D52(%rip),%r12
  call   <puts@plt>
  lea    D0(%rip),%rdi
  call   <puts@plt>
  lea    D48(%rip),%rdi
  call   <puts@plt>
  lea    D40(%rip),%rdi
  call   <puts@plt>
  lea    D140(%rip),%rdi
  call   <puts@plt>
  lea    D17(%rip),%rdi
  call   <puts@plt>
  lea    D19(%rip),%rdi
  call   <puts@plt>
  mov    %ebp,%esi
  lea    D66(%rip),%rdi
  xor    %eax,%eax
  call   <printf@plt>
  mov    %r12,%rdi
  call   <puts@plt>
  xor    %eax,%eax
  call   <getchar@plt>
  xor    %eax,%eax
  call   <setup_io@plt>
  xor    %eax,%eax
  call   <setup_gpio@plt>
  xor    %eax,%eax
  call   <setup_spi@plt>
  xor    %esi,%esi
  mov    %ebp,%edi
  call   <write_dac@plt>
  lea    D15(%rip),%rdi
  call   <puts@plt>
  mov    %r12,%rdi
  call   <puts@plt>
  xor    %eax,%eax
  call   <getchar@plt>
  mov    $0x400,%esi
  mov    %ebp,%edi
  call   <write_dac@plt>
  lea    D94(%rip),%rdi
  call   <puts@plt>
  mov    %r12,%rdi
  call   <puts@plt>
  xor    %eax,%eax
  call   <getchar@plt>
  mov    $0x7f0,%esi
  mov    %ebp,%edi
  call   <write_dac@plt>
  lea    D58(%rip),%rdi
  call   <puts@plt>
  mov    %r12,%rdi
  call   <puts@plt>
  xor    %eax,%eax
  call   <getchar@plt>
  mov    $0xaa0,%esi
  mov    %ebp,%edi
  call   <write_dac@plt>
  lea    D70(%rip),%rdi
  call   <puts@plt>
  mov    %r12,%rdi
  call   <puts@plt>
  xor    %eax,%eax
  call   <getchar@plt>
  mov    $0xff0,%esi
  mov    %ebp,%edi
  call   <write_dac@plt>
  lea    D73(%rip),%rdi
  call   <puts@plt>
  mov    %r12,%rdi
  call   <puts@plt>
  xor    %eax,%eax
  call   <getchar@plt>
  pop    %rbx
  xor    %eax,%eax
  pop    %rbp
  pop    %r12
  jmp    1130 <restore_io@plt>
```

tool_calls: name: parse_data
arguments: data_label: D21
type_infered: string
name: parse_data
arguments: data_label: D46
type_infered: string
name: parse_data
arguments: data_label: D52
type_infered: string
name: parse_data
arguments: data_label: D0
type_infered: string
name: parse_data
arguments: data_label: D48
type_infered: string
name: parse_data
arguments: data_label: D40
type_infered: string
name: parse_data
arguments: data_label: D140
type_infered: string
name: parse_data
arguments: data_label: D17
type_infered: string
name: parse_data
arguments: data_label: D19
type_infered: string
name: parse_data
arguments: data_label: D66
type_infered: string
name: parse_data
arguments: data_label: D15
type_infered: string
name: parse_data
arguments: data_label: D94
type_infered: string
name: parse_data
arguments: data_label: D58
type_infered: string
name: parse_data
arguments: data_label: D70
type_infered: string
name: parse_data
arguments: data_label: D73
type_infered: string

tool: D21: Which channel do you want to test? Type 0 or 1.

tool: D46: These are the connections for the digital to analogue test:

tool: D52: When ready hit enter.

tool: D0: jumper connecting GP11 to SCLK

tool: D48: jumper connecting GP10 to MOSI

tool: D40: jumper connecting GP9 to MISO

tool: D140: jumper connecting GP7 to CSnB

tool: D17: Multimeter connections (set your meter to read V DC):

tool: D19:   connect black probe to GND

tool: D66:   connect red probe to DA%d on J29


tool: D15: Your meter should read about 0V

tool: D94: Your meter should read about 0.5V

tool: D58: Your meter should read about 1.02V

tool: D70: Your meter should read about 1.36V

tool: D73: Your meter should read about 2.04V

assistant: ```c
void main(void) {
  int d, chan, dummy;
  do {
    printf("Which channel do you want to test? Type 0 or 1.\n");
    chan = (int)getchar();
    (void)getchar();
  } while (chan != '0' && chan != '1');
  chan = chan - '0';
  printf("These are the connections for the digital to analogue test:\n");
  printf("jumper connecting GP11 to SCLK\n");
  printf("jumper connecting GP10 to MOSI\n");
  printf("jumper connecting GP9 to MISO\n");
  printf("jumper connecting GP7 to CSnB\n");
  printf("Multimeter connections (set your meter to read V DC):\n");
  printf("  connect black probe to GND\n");
  printf("  connect red probe to DA%d on J29\n", chan);
  printf("When ready hit enter.\n");
  (void)getchar();
  setup_io();
  setup_gpio();
  setup_spi();
  d = 0x000;
  write_dac(chan, d);
  printf("Your meter should read about 0V\n");
  printf("When ready hit enter.\n");
  (void)getchar();
  d = 0x400;
  write_dac(chan, d);
  printf("Your meter should read about 0.5V\n");
  printf("When ready hit enter.\n");
  (void)getchar();
  d = 0x7F0;
  write_dac(chan, d);
  printf("Your meter should read about 1.02V\n");
  printf("When ready hit enter.\n");
  (void)getchar();
  d = 0xAA0;
  write_dac(chan, d);
  printf("Your meter should read about 1.36V\n");
  printf("When ready hit enter.\n");
  (void)getchar();
  d = 0xFF0;
  write_dac(chan, d);
  printf("Your meter should read about 2.04V\n");
  printf("When ready hit enter.\n");
  (void)getchar();
  restore_io();
}
```