Table 17-13. High-Voltage Serial Programming Instruction Set for ATtiny13 (Continued)

Note: a = address high bits, b = address low bits, d = data in high bits, e = data in low bits, p = data out high bits, q = data out low bits, x = don’t care, 1 = Lock Bit1, 2 = Lock Bit2, 3 = CKSEL0 fuse, 4 = CKSEL1 fuse, 5 = SUT0 fuse, 6 = SUT1 fuse, 7 = CKDIV8, fuse, 8 = WDTON fuse, 9 = EESAVE fuse, A = SPIEN fuse, B = RSTDISBL fuse, C = BODLEVEL0 fuse, D= BODLEVEL1 fuse, E = MONEN fuse, F = SELFPRGEN fuse

Note: The EEPROM is written page-wise. But only the bytes that are loaded into the page are actually written to the EEPROM. Pagewise EEPROM access is more efficient when multiple bytes are to be written to the same page. Note that auto-erase of EEPROM is not available in High-voltage Serial Programming, only in SPI Programming.

17.8Considerations for Efficient Programming

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

•The command needs only be loaded once when writing or reading multiple memory locations.

•Skip writing the data value 0xFF that is the contents of the entire EEPROM (unless the EESAVE fuse is programmed) and Flash after a Chip Erase.

•Address High byte needs only be loaded before programming or reading a new 256 word window in Flash or 256 byte EEPROM. This consideration also applies to Signature bytes reading.

17.8.1Chip Erase

The Chip Erase will erase the Flash and EEPROM(1) memories plus lock bits. The lock bits are not reset until the Program memory has been completely erased. The fuse bits are not changed. A Chip Erase must be performed before the Flash and/or EEPROM are re-programmed.

1.Load command “Chip Erase” (see Table 17-13 on page 110).

2.Wait after Instr. 3 until SDO goes high for the “Chip Erase” cycle to finish.

3.Load Command “No Operation”.

Note: 1. The EEPROM memory is preserved during Chip Erase if the EESAVE fuse is programmed.

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Figure 17-4. High-voltage Serial Programming Waveforms

17.8.3Programming the EEPROM

The EEPROM is organized in pages, see Table 18-8 on page 121. 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 (refer to Table 17-13 on page 110):

1.Load Command “Write EEPROM”.

2.Load EEPROM Page Buffer.

3.Program EEPROM Page. Wait after Instr. 2 until SDO goes high for the “Page Programming” cycle to finish.

4.Repeat 2 through 3 until the entire EEPROM is programmed or until all data has been programmed.

5.End Page Programming by Loading Command “No Operation”.

17.8.4Reading the Flash

The algorithm for reading the Flash memory is as follows (refer to Table 17-13 on page 110):

1.Load Command "Read Flash".

2.Read Flash Low and High Bytes. The contents at the selected address are available at serial output SDO.

17.8.5Reading the EEPROM

The algorithm for reading the EEPROM memory is as follows (refer to Table 17-13 on page 110):

1.Load Command “Read EEPROM”.

2.Read EEPROM Byte. The contents at the selected address are available at serial output SDO.

17.8.6Programming and Reading the Fuse and Lock Bits

The algorithms for programming and reading the fuse low/high bits and lock bits are shown in

Table 17-13 on page 110.

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