In-system programming is the ability of programming IC which is already soldered in circuit using serial programming algorithms. The major advantage of ISP programming is that the manufacturer can have single production phase, eliminating programming stage prior to assembling the system.
Code or design changes are also possible during the production process without the need of de soldering the chip by reprogramming the chip which is already installed on target PCB. Xeltek ISP programmer; SuperPro IS01, is a portable, stand-alone, self-powered universal ISP programmer. It supports most ISP protocols, e.g. I2C, SPI, UART, BDM, MW, JTAG, CAN, RS232 etc and also operates in standalone mode using SD cards. It comes with standard ATE (Automated Test Equipment) which provides the possibility of operating and controlling programmer through external signals. This article will help you to understand ATE interface and its functionality in a better way.
ATE control port is used for communication with external host or integration into the automatic programming or test equipment. Therefore, besides the keyboard, the user can also operate ISP programmer through ATE interface. ATE equipment interface adopts opto-coupling device to isolate signals, in order to ensure security and accuracy of signals between the two equipments. In addition, while using ATE interface, it is required to set the power voltage of external equipment signal and appropriate reference voltage point correctly.
The pinout for ATE port:

For the signals of ATE port, please refer to the diagram below:

Description of signals:
OPTO_VCC: Working power of ATE controlling port is supplied by exterior controlling equipment and it should match signal voltage.
SEL0-SEL5: These input signals are used to select project file which is already stored on SD card.
START, RESET: These are Input signals discussed later.
PASS, FAIL: These are output signals discussed later.
OPTO_GND1: Exterior controlling equipment GND1, which is used to input signals of SEL0-SEL5, START and RESET.
OPTO_GND2:Exterior controlling equipment GND2, which is used to output signals of PASS and FAIL.
VCC, GND:IS01 supplies 3.3V output, GND output
When the system starts, it performs initialization until “XELTEK IS01” is shown on display screen. After that, it will be testing interface of USB, keyboard and ATE all the time. If any of the signals SEL0-SEL5 of ATE interface is high, then IS01 will enter ATE work mode.
Create a project:
Create a project by SPIS01 software. After the project is generated, it can be downloaded into SD card by SPIS01 software or a card reader.
ATE workflow chart

Project Selection:
SEL0-SEL5 of IS01 ATE interface is used to select projects. Using binary format; from 1 to 63, means, user can select no more than 63 projects. For example, if SEL0 is high and the others are low, project# 1 is selected; if both SEL0 and SEL1 are high, the others are low, project# 3 is selected, etc…
Run algorithm:
After User selects the project, set pin START high, then the system starts programming.
Thus, we can witness ATE interface is built for easy external hardware control which utilizes standalone feature of SuperPro IS01 programmer. Total of 6 signal lines SEL0 to SEL5 are for project selection (maximum 64 project files); 2 command lines for START and STOP; 3 STATUS lines such as PASS, FAIL and BUSY. All signals are optical-isolated thus providing noise free operation.