User guide

Arch Meter Corporation PS1000 Ver1.2
PS1000Rev. 1.2 May 2006
31/ 67
www.archmeter.com
SPISTA(SFR 0xBE)
B7 B6 B5 B4 B3 B2 B1 B0
SPIF WCOL MODF x x x x x
SPIF SPI data transfer flag
1: the data transfer has been completed
0: data transfer is in progress or the status register has been read by
controller
WCOL Write Collision Flag
1: a collision has been detected
0: no collision has occurred or the status register has been read by
controller
MODF Mode Fault, it can only be cleared by disabling the SPI
1: the SS pin is at inappropriate logic level
0: the SS pin is at appropriate logic level
For the SPI interface, one master could connect with several slave devices.
Here is the connection diagram. All slave devices share the SCK, MISO(SI) and
MOSI(SO) bus. But for the SS control signal, each slave device must control
individually.
SCK
MISO
MOSI
SS
Port0
Port1
Port2
Port3
VDD
SCK
MISO
MOSI
SS
SCK
MISO
MOSI
SS
SCK
MISO
MOSI
SS
SCK
MISO
MOSI
SS