3.10.12.6 High-Voltage Serial Programming

The High-Voltage Serial Programming (HVSP) mode allows memories, fuses and lock bits to be programmed. To enter the HVSP mode, a special test signature has to be applied on the ATA8510/15.

Entering the High-Voltage Serial Programming Mode

The following algorithm is recommended for entering HVSP mode:

1. Set all test signature pins (TESTSIG0 … TESTSIG3) to ‘0’.
2. Set NRESET and TEST_EN pins to ‘0’.
3. Apply 2.4-5.5V between VS and GND.
4. Wait 1-4 ms.
5. Set TEST_EN to 2.4V – 3.3V and NRESET to VS (HIGH). The TEST_EN pin is damaged if voltages higher than 3.3V are applied. A lower voltage than the voltage on VS shall be used for TEST_EN. VS_PA must be set to the same voltage as TEST_EN.
6. Keep the test signature pins unchanged for at least 10 µs.
7. Release all test signature pins.
8. Execute the desired HVSP commands.
9. Exit programming by powering down the device.

Considerations for Efficient Programming

The loaded command and address are retained in the device during programming. For efficient programming, the following items must be considered:

• The command only needs to be loaded once when writing or reading multiple memory locations.
• Skip writing the data value 0xFF because this is the content of the entire EEPROM (unless the EESAVE fuse is programmed) and Flash after a chip erase.
• The address high byte only needs to be loaded before programming or reading a new 256-word window in Flash or 256-byte EEPROM. This consideration also applies to reading signature bytes.

Chip Erase

The CHIP ERASE command erases the Flash, the EEPROM and the lock bits. The lock bits are not reset until the program memory is completely erased. The fuse bits are not changed. A chip erase must be performed before the Flash and/or EEPROM are reprogrammed.

The EEPROM memory is preserved during chip erase if the EESAVE fuse is programmed. The following procedure describes how to execute a “chip erase”:

1. Load the CHIP ERASE command (see Table 3-115).
2. After instruction 3, wait until SDO goes HIGH for the chip erase cycle to finish.
3. Load the NO OPERATION command.

Programming the Flash

The Flash is organized in pages, see the In-System Re-programmable Flash Program Memory (ATA8510). When programming the Flash, the program data is latched into a page buffer. This allows one page of program data to be programmed simultaneously. The following procedure describes how to program the entire Flash memory:

1. Load the WRITE FLASH command (see the following table)
2. Load the Flash page buffer.
3. Load the Flash high address and program page. After instruction 3, wait until SDO goes HIGH for the page programming cycle to finish.
4. Repeat 2 through 3 until the entire Flash is programmed or until all data is programmed.
5. Terminate page programming by loading the NO OPERATION command.

When writing or reading serial data to the ATA8510, data is clocked on the rising edge of the serial clock.

Programming the EEPROM

The EEPROM is organized in pages as described in the EEPROM Data Memory. When programming the EEPROM, the data is latched into a page buffer. This allows one page of data to be programmed simultaneously. The programming algorithm for the EEPROM data memory is as follows (see the following table):

1. Load command “Write EEPROM”.
2. Load EEPROM page buffer.
3. Program EEPROM page. Wait after Instruction 2 until SDO goes high for the “Page Programming” cycle to finish.
4. Repeat instruction 2 through 3 until the entire EEPROM is programmed or until all data is programmed.
5. Terminate page programming by loading command “No Operation”.

Reading the Flash

The algorithm for reading the Flash memory is as follows (see the following table):

1. Load the READ FLASH command.
2. Read the Flash low and high bytes. The contents at the selected address are available at serial output SDO.

Reading the EEPROM

The algorithm for reading the EEPROM memory is as follows (see the following table):

1. Load the command “Read EEPROM”.
2. Read EEPROM byte. The contents at the selected address are available at serial output SDO.

Programming and Reading the Fuse and Lock Bits

The algorithms for programming and reading the fuse low/high bits and lock bits display in the following table.

Reading the Signature Bytes and Calibration Byte

The algorithms for reading the signature bytes and the calibration byte display in the following table.

HVSP Instruction Overview