Datasheet

 2018 Microchip Technology Inc. Data Sheet Complete DS40002060A-page 115
ATtiny4/5/9/10
16. Memory Programming
16.1 Features
• Two Embedded Non-Volatile Memories:
– Non-Volatile Memory Lock bits (NVM Lock bits)
– Flash Memory
• Four Separate Sections Inside Flash Memory:
– Code Section (Program Memory)
– Signature Section
– Configuration Section
– Calibration Section
• Read Access to All Non-Volatile Memories from Application Software
• Read and Write Access to Non-Volatile Memories from External programmer:
– Read Access to All Non-Volatile Memories
– Write Access to NVM Lock Bits, Flash Code Section and Flash Configuration Section
• External Programming:
– Support for In-System and Mass Production Programming
– Programming Through the Tiny Programming Interface (TPI)
• High Security with NVM Lock Bits
16.2 Overview
The Non-Volatile Memory (NVM) Controller manages all access to the Non-Volatile Memories. The NVM Controller con-
trols all NVM timing and access privileges, and holds the status of the NVM.
During normal execution the CPU will execute code from the code section of the Flash memory (program memory). When
entering sleep and no programming operations are active, the Flash memory is disabled to minimize power consumption.
All NVM are mapped to the data memory. Application software can read the NVM from the mapped locations of data mem-
ory using load instruction with indirect addressing.
The NVM has only one read port and, therefore, the next instruction and the data can not be read simultaneously. When
the application reads data from NVM locations mapped to the data space, the data is read first before the next instruction is
fetched. The CPU execution is here delayed by one system clock cycle.
Internal programming operations to NVM have been disabled and the NVM therefore appears to the application software
as read-only. Internal write or erase operations of the NVM will not be successful.
The method used by the external programmer for writing the Non-Volatile Memories is referred to as external program-
ming. External programming can be done both in-system or in mass production. See Figure 15-2 on page 105. The
external programmer can read and program the NVM via the Tiny Programming Interface (TPI).
In the external programming mode all NVM can be read and programmed, except the signature and the calibration sections
which are read-only.
NVM can be programmed at 5V, only.
16.3 Non-Volatile Memories
The ATtiny4/5/9/10 have the following, embedded NVM:
• Non-Volatile Memory Lock Bits
• Flash memory with four separate sections