Ocean Optics Flame-S, User Manual

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8: Firmware and Advanced Communications
76 225-00000-000-11-201604
General SPI Input/Output
Performs a general-purpose write and read on the SPI bus for interfacing to attached
peripherals. The time to complete the command is determined by the amount of data
transferred and the response time of the peripheral. Wait at least 10 ms after sending a Write
command before reading the Return value. The SPI bus runs at ~125KHz Clock. The maximum
number of bytes that can be written or read is 61. During this transfer the SPI Chip Select
signal is driven to an active LOW TTL level. Data is transmitted out the MOSI (Master Out Slave
In) line on the rising edge of the clock signal. Data is also latched in the from the MISO line on
the falling edge of the clock signal.
Command Byte Format
Byte 0 Byte 1 Byte 2 Byte 3 … Byte N+2
0x62
# of Bytes (N) Write Byte 0 Write Byte 1
…
Write Byte
N
Return Byte Format
Byte 0 Byte 1 Byte 2 … Byte N+1
# of Bytes (N) Read Byte 0 Read Byte 1
…
Read Byte N
Write Register Information
Most all of the controllable parameters for the Flame are accessible through this command
(e.g., GPIO, strobe parameters, etc.). A complete list of these parameters with the associate
register information is shown in the table below. Commands are written to End Point 1 Out
typically with 4 bytes (some commands may require more data bytes). All data values are 16 bit
values transferred in LSB | MSB order. This command requires 100us to complete; the calling
program needs to delay for this length of time before issuing another command. In some
instances, other commands will also write to these registers (i.e., integration time), in these
cases the user has the options of setting the parameters through 2 different methods.
Byte Format
Byte 0 Byte 1 Byte 2 Byte 3
0x6A
Register
Value Data Byte LSB Data Byte
MSB