NXP Flash MCU to Atmel Flash MCU Cross Reference. 07/01/ 86KB. NXP Flash MCU to Atmel Flash MCU Devices, Non-Direct Replacements. 07/01/ The device is manufactured using Atmel’s high density nonvolatile memory technology and is compatible with the industry standard 80C51 instruction set and. 89C55 datasheet, 89C55 circuit, 89C55 data sheet: ATMEL – 8-Bit Microcontroller with 20K Bytes Flash,alldatasheet, datasheet, Datasheet search site for.
|Published (Last):||28 January 2012|
|PDF File Size:||11.39 Mb|
|ePub File Size:||20.51 Mb|
|Price:||Free* [*Free Regsitration Required]|
Note, however, that one ALE pulse is skipped during each access to external data mem- ory. The AT89C55 provides the following standard features: In addition, the AT89C55 is designed with static logic for operation down to zero frequency and sup- ports two software selectable power saving modes.
Aymel external interrupt 1. Note that stack operations are examples of indirect addressing, so the upper bytes of data RAM are avail- able as stack space. External pullups are required during program verifica- tion. Port 2 emits the high-order address byte during fetches from external program memory 89f55 during accesses to external data memory that use bit addresses MOVX DPTR.
At89c55-24jc Atmel IC Microcontroller 8-bit 44 Pin PLCC MCU 89c55-24jc
As an output port, each pin can sink eight TTL aatmel. Read accesses to these addresses will in general return random data, and write accesses will have an indetermi- nate effect. Setting the ALE-disable bit has no effect if the microcontroller is in external execution mode. The device is manu- factured using Atmel’s high density nonvolatile memory technology and is compatible with the industry standard 80C51 instruction set and pinout. Instructions that use direct addressing access SFR space.
Port 0 also receives the code bytes during Flash program- ming and outputs the code bytes during program verifica- tion. Atmle timer 0 external input.
When 1s are written to Port 2 pins, they are pulled high by the internal pullups and can be used as inputs. Interrupt Registers The individual interrupt enable bits are in the IE register.
RXD serial input port. A high on this pin for two machine cycles while the oscillator is running resets aatmel device. The on-chip Flash allows the program memory to be 89f55 in-system or by a conventional nonvolatile memory programmer. Note that not all of the addresses are occupied, and unoc- cupied addresses may not be implemented on the chip.
This pin also receives the volt programming enable volt- age V. When 1s are written to port 0 pins, the pins can be used as high- impedance inputs.
atml User software should not write 1s to these unlisted loca- tions, since they may be used in future products to invoke new features. RD external data memory read strobe. Note, however, that if lock bit 1 is programmed, EA will be internally latched on reset.
Port 3 also receives the highest-order address bit and some control signals for Flash ztmel and verifica- tion. As inputs, Port 3 pins that are externally being pulled low will source current I.
WR external data memory write strobe. TXD serial output port. In that case, the reset or inactive values of the new bits will always be 0. The upper bytes occupy a parallel address space to the Special Function Registers.
XTAL2 Output from the inverting oscillator amplifier. As inputs, Port 1 pins that are externally being pulled low will source current I. The Power Down Mode saves the RAM con- tents but freezes the oscillator, disabling all other chip func- tions until the next hardware reset. The low-voltage option saves power and operates with a 2.
When 1s are written to Port 1 pins, they are pulled high by the internal 98c55 and can be used as inputs. INT0 external interrupt 0.
At89cjc Atmel IC Microcontroller 8-bit 44 Pin PLCC MCU 89cjc | eBay
Port 2 also receives the high-order address bits and some control signals during Flash programming and verification. Otherwise, the pin is weakly pulled high. Port 1 also receives the low-order address bytes during Flash programming and verification. For example, the following indirect addressing instruction, where R0 contains 0A0H, accesses the data byte at address 0A0H, rather than P2 whose address is 0A0H.
Port 3 also serves the functions of various special features of the AT89C55, as shown in the following table. As inputs, Port 2 pins that are externally being pulled low will source current I.
When 1s are written to Port 3 pins, they are pulled high by the internal pullups and can be used as inputs. Two priorities can be set for each of the six interrupt sources in the IP register.
In this application, Port 2 uses strong internal pul- lups when emitting 1s. Instructions that use indirect addressing access the upper bytes of RAM.
89C55 (ATMEL) – 8-bit Microcontroller With 20k Bytes Flash | eet
T1 timer 1 external input. In this mode, P0 has internal pul- lups. XTAL1 Input to the inverting oscillator amplifier and input to the internal clock operating circuit. Three-Level Program Memory Lock. EA should be strapped atmep V. Search field Part name Part description. By combining a versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89C55 is a powerful microcomputer which provides a highly flexible and cost effective solution to many embedded control applications.