INFICON Spot CDS550D - Manual (Page 9)

Research & Development
SPOT CDS500D & CDS550D OEM Sensor SPI-Interface Specification_V1.1 Page 9 of 14
Christian Berg, T based on Felix Mullis, TL Created 11/10/2014 2:36:00 PM
3.3 Status and Error
The SPI communication string for reading the status value consists of total 4 bytes as follows:
0x48 – 0x00 – 0x00 – 0x00, only the first byte is relevant, the other three must be sent but the content
of them doesn’t matter.
Read Status Op-Code:
Byte_3 Byte_2 Byte_1 Byte_0
0 1 0 0 1 0 0 0 don’t care
Status result:
Byte_3 Byte_2 Byte_1 Byte_0
don’t’ care 24-Bit Status value (Bit 23..0)
Bit
Description
23 SPI communication took place during measurement
13 Pressure error
8 port 3 error
7 port 2 error
6 port 1 error
5 port 0 error
3 Temperature error
All other bits not mentioned here must be ignored.
3.4 Power-up reset
After powering up the device, it must be reset by sending the reset command to the device. The reset
command consists of the single byte 0x88h. It is highly recommended to send the reset command
(0x88h) to the sensor after every power up.
4 History
Ver-
sion
Date by Contents
1.0 Jan 17, 2014
Christian
Berg
initial version
1.1 Nov 10, 2014 Felix Mullis timing specification in section 2.4 and 5.2