diff options
| author | David A. Mellis <d.mellis@arduino.cc> | 2010-08-11 22:59:00 +0000 |
|---|---|---|
| committer | David A. Mellis <d.mellis@arduino.cc> | 2010-08-11 22:59:00 +0000 |
| commit | 6b6d46c3e1fa2c05aee87d84c197ea620efb7370 (patch) | |
| tree | 0b72598ea83e7aaa3677ed5b4978ad52643d377c /cores/arduino/wiring_shift.c | |
| parent | 8dca3d5ad33b8ba7de070a0a0481ac9763c323a6 (diff) | |
Adding shiftIn() from Wiring (no count or delaytime though).
Diffstat (limited to 'cores/arduino/wiring_shift.c')
| -rwxr-xr-x | cores/arduino/wiring_shift.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/cores/arduino/wiring_shift.c b/cores/arduino/wiring_shift.c index 956f864..cfe7867 100755 --- a/cores/arduino/wiring_shift.c +++ b/cores/arduino/wiring_shift.c @@ -24,9 +24,24 @@ #include "wiring_private.h" -void shiftOut(uint8_t dataPin, uint8_t clockPin, uint8_t bitOrder, byte val) +uint8_t shiftIn(uint8_t dataPin, uint8_t clockPin, uint8_t bitOrder) { + uint8_t value = 0; + uint8_t i; + + for (i = 0; i < 8; ++i) { + digitalWrite(clockPin, HIGH); + if (bitOrder == LSBFIRST) + value |= digitalRead(dataPin) << i; + else + value |= digitalRead(dataPin) << (7 - i); + digitalWrite(clockPin, LOW); + } + return value; +} + +void shiftOut(uint8_t dataPin, uint8_t clockPin, uint8_t bitOrder, uint8_t val) { - int i; + uint8_t i; for (i = 0; i < 8; i++) { if (bitOrder == LSBFIRST) |