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):||16 March 2016|
|PDF File Size:||10.12 Mb|
|ePub File Size:||8.24 Mb|
|Price:||Free* [*Free Regsitration Required]|
89C55 Datasheet pdf – 8-Bit Microcontroller with 20K Bytes Flash – Atmel
INT1 external interrupt 1. Port 3 also receives the highest-order address bit and some control signals for Flash programming and verifica- tion. User software should not write 1s to these unlisted loca- tions, since they may be used in future products to invoke new features.
T1 timer 1 external input. The Power Down Mode saves the RAM con- tents but freezes the oscillator, disabling all other chip func- tions until the next hardware reset.
XTAL1 Input to the inverting oscillator amplifier and input to the internal clock operating circuit. Two priorities can be set for each of the six interrupt sources in the IP register. TXD serial output port.
When 1s are written to Port 1 pins, they are pulled high by the internal pullups and 889c55 be used as inputs. Port 3 also serves the functions of various special features of the AT89C55, as shown in the following table.
INT0 external interrupt 0. For example, the following indirect addressing instruction, where R0 contains 0A0H, accesses the aymel byte at address 0A0H, rather than P2 whose address is 0A0H. Port 2 emits the high-order address byte during fetches from external program memory and during accesses to external data memory that use bit addresses MOVX DPTR. As inputs, Port 3 pins that are externally being pulled low will source current I. The low-voltage option saves power and operates with a 2.
In this mode, P0 has internal pul- lups. 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.
Note, however, that one ALE pulse is skipped during each access to external tamel mem- ory. When 1s are written to Port 3 pins, they are pulled high by the internal pullups and can atmeel used as inputs. External pullups are required during program verifica- tion. 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.
EA should be strapped to V.
At89c55-24jc Atmel IC Microcontroller 8-bit 44 Pin PLCC MCU 89c55-24jc
Note, however, that if lock bit 1 is programmed, EA will be internally latched on reset. A high on this pin for two machine cycles while the oscillator is running resets the device.
As inputs, Port 2 pins that are externally being pulled low will source current I. The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional nonvolatile memory programmer. As inputs, Port 1 pins that are externally being pulled low will source current I. When 1s are written to Port 2 pins, they are pulled high by the internal pullups and can be used as inputs. As an output port, each 895c5 can sink eight TTL inputs.
Read accesses to these addresses will in general return random data, and write accesses will have an indetermi- nate effect. XTAL2 Output from the inverting oscillator amplifier. In addition, the AT89C55 is designed atnel static logic for operation down to zero frequency and sup- ports two software selectable power saving modes. Search field Part name Part description. Atmmel pin also receives the volt programming enable volt- age V. Port 2 also receives the high-order atjel bits and 89cc55 control signals during Flash programming and verification.
Setting the ALE-disable bit has no effect if the microcontroller is in external execution mode. The upper bytes occupy a parallel address space to the Special Function Registers. In this application, Port 2 uses strong internal pul- lups when emitting 1s.
In that case, the atmwl or inactive values of the new bits will always be 0. Interrupt Registers 8c955 individual interrupt enable bits are in the IE register. Port 1 also receives the low-order address bytes during Flash programming and verification.
Note that not all of the addresses are occupied, and unoc- cupied addresses may not be implemented on the chip. RD external data memory read strobe. Instructions that use direct addressing access SFR space. Three-Level Program Memory Lock.
WR external data memory write strobe. The AT89C55 provides the following standard features: