Memory layout of a data structure: Difference between revisions
Memory layout of a data structure (view source)
Revision as of 20:50, 7 December 2011
, 12 years agoGo solution
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Of course, this is a very simplified view of the full RS-232 protocol. Also, although this represents the order of the pins in a D-9 connector, this would not necessarily be the same as the order of the bits in a control register.
=={{header|Go}}==
Go does not have named bits as part of the type system. Instead, constants are typically defined as shown. For a word of bits with special meanings like this, a type would be defined though, as shown. Static typing rules then control assignments and comparisons at the word level. At the bit level, it helps to follow naming conventions so that, say, using a 9-pin constant on a 25-pin word would be an obvious error in the source code.
<lang go>package main
import "fmt"
type rs232p9 uint16
const (
CD9 = 1 << iota // Carrier detect
RD9 // Received data
TD9 // Transmitted data
DTR9 // Data terminal ready
SG9 // signal ground
DSR9 // Data set ready
RTS9 // Request to send
CTS9 // Clear to send
RI9 // Ring indicator
)
func main() {
// set some nonsense bits just for example
var p rs232p9 = RI9 | TD9 | CD9
fmt.Printf("%04x\n", p)
}</lang>
Output:
<pre>
0105
</pre>
=={{header|J}}==
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