# Registers

Registers all begin with a dollar-symbol ($). The floating point registers are named $f0, $f1, ..., $f31. The general-purpose registers have both names and numbers, and are listed below. When programming in MIPS assembly, it is usually best to use the register names.

<table><thead><tr><th width="126.33333333333331">Number</th><th width="146">Name</th><th>Comments</th></tr></thead><tbody><tr><td>$0</td><td>$zero, $r0</td><td>Always zero</td></tr><tr><td>$1</td><td>$at</td><td>Reserved for assembler</td></tr><tr><td>$2, $3</td><td>$v0, $v1</td><td>First and second return values, respectively</td></tr><tr><td>$4, ..., $7</td><td>$a0, ..., $a3</td><td>First four arguments to functions</td></tr><tr><td>$8, ..., $15</td><td>$t0, ..., $t7</td><td>Temporary registers</td></tr><tr><td>$16, ..., $23</td><td>$s0, ..., $s7</td><td>Saved registers</td></tr><tr><td>$24, $25</td><td>$t8, $t9</td><td>More temporary registers</td></tr><tr><td>$26, $27</td><td>$k0, $k1</td><td>Reserved for kernel (operating system)</td></tr><tr><td>$28</td><td>$gp</td><td>Global pointer</td></tr><tr><td>$29</td><td>$sp</td><td>Stack pointer</td></tr><tr><td>$30</td><td>$fp</td><td>Frame pointer</td></tr><tr><td>$31</td><td>$ra</td><td>Return address</td></tr></tbody></table>

In addition to the general purpose registers, the MIPS32 architecture also includes a number of special purpose registers, which are used to control the operation of the processor and to store certain types of data. These include the **program counter (PC) and** the **status register (SR).**

## Resources

{% embed url="<https://www.mips.com/products/architectures/mips32-2/>" %}


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