BASIC stamp manual v2.2

5: BASIC Stamp Command Reference – SHIFTOUT
BASIC Stamp Syntax and Reference Manual 2.2 www.parallax.com Page 435
SHIFTOUT
BS1 BS2 BS2e BS2sx BS2p BS2pe BS2px
SHIFTOUT Dpin, Cpin, Mode, [ OutputData { \Bits } { ,OutputData { \Bits }} ]
Function
Shift data out to a synchronous serial device.
Dpin is a variable/constant/expression (0 – 15) that specifies the I/O
pin that will be connected to the synchronous serial device’s data
input. This pin will be set to output mode.
Cpin is a variable/constant/expression (0 – 15) that specifies the I/O
pin that will be connected to the synchronous serial device’s clock
input. This pin will be set to output mode.
Mode is a variable/constant/expression (0 – 1), or one of two
predefined symbols, that tells SHIFTOUT the order in which data
bits are to be arranged. See Table 5.117 for value and symbol
definitions.
OutputData is a variable/constant/expression containing the data to
be sent.
Bits is an optional variable/constant/expression (1 – 16) specifying
how many bits are to be output by SHIFTOUT. When the Bits
argument is given, the BASIC Stamp transmits the rightmost
number of bits specifed, regardless of the Mode. If no Bits argument
is given, SHIFTOUT defaults to 8 bits.
Quick Facts
Table 5.116: SHIFTOUT Quick
Facts.
BS2, BS2e BS2sx, BS2p BS2pe BS2px
Timing of t
h
and t
l
,
14 µs / 46 µs 5.6 µs / 18 µs 14 µs / 46 µs
3.6 µs / 11.8 µs
Timing of t
a
and t
b
15 µs / 30 µs 6.3 µs / 12.5 µs 15 µs / 30 µs 4 µs / 7.8 µs
Transmission Rate
~16 kbits/sec. ~42 kbits/sec. ~16 kbits/sec. ~65 kbits/sec.
Related Command
SHIFTOUT
Explanation
SHIFTIN and SHIFTOUT provide an easy method of acquiring data from
synchronous serial devices. Synchronous serial differs from asynchronous
serial (like SERIN and SEROUT) in that the timing of data bits (on a data
line) is specified in relationship to clock pulses (on a clock line). Data bits
may be valid after the rising or falling edge of the clock line. This kind of
All
2