Linear Sensor Array Using the TSL3301 DeviceSubmitted to Parallax by Phil Pilgrim
Phil Pilgrim designed the Texas Advanced Optical Systems (TAOS) TSL3301 Evaluation Kit. The kit uses an SX18AC/DP to interface to the TAOS TSL3301 linear sensor array. The TAOS TSL3301 Evaluation Kit is available as a commercial product and may be purchased from TAOS. The SX18AC/DP source code was released under the GNU public license, so you could actually buy a TSL3301 Evaluation Kit and experiment with the SX's source code (written with SASM).
The TAOS TSL3301 is intended to simplfy image sensing applications by providing an 8-bit digital output in serial format, but interfacing to the linear image sensor requires a high-speed microcontroller with bit-banged serial routines. All communication with the TSL3301 occurs using three digital (TTL-compatible) lines: SDIN, the serial data input to the sensor; SDOUT, the serial data output from the sensor; and SCLK, the serial data clock. The protocol is isosynchronous. That is to say, even though a synchronous clock is used at the bit level to clock data into and out of the device, the data itself contains additional byte synchronization cues in the form of start and stop bits. Each 8-bit data packet is preceded by a single, 0-level start bit and is followed by a single 1-level stop bit. Therefore each byte transfer requires 10 clocks. This required the high speed of the SX microcontroller. |