5.5.2.4 .skip size[, fill] 
.space size[, fill]

Reserve size bytes. Each byte is filled with the value fill.

fill is optional. If the value specified for fill is larger than a byte, a warning is displayed and the value is truncated to a byte. If not specified:

• In a data section, a value of 0x00 is used to fill the skipped bytes.
• In a code section, the last specified .fillvalue is used to fill the skipped bytes.