Electronic Components Datasheet Search |
|
HT82B40R Datasheet(PDF) 11 Page - Holtek Semiconductor Inc |
|
HT82B40R Datasheet(HTML) 11 Page - Holtek Semiconductor Inc |
11 / 58 page HT82B40R/HT82B40A Rev. 1.50 11 February 17, 2011 Special Purpose Data Memory This area of Data Memory is where registers, necessary for the correct operation of the microcontroller, are stored. It is divided into two banks, Bank 0 and Bank1. Most of the registers are both readable and writeable but some are protected and are readable only, the de- tails of which are located under the relevant Special Function Register section. Note that for locations that are unused, any read instruction to these addresses will return the value ²00H². The Special Purpose Registers for the USB interface are stored in Bank 1 which can only be accessed by first setting the Bank Pointer to a value of 01H and then us- ing Indirect Addressing Register IAR1 and Memory Pointer MP1. Bank 1 can only be accessed indirectly us- ing the MP1 Memory Pointer, direct addressing is not possible. Special Function Registers To ensure successful operation of the microcontroller, certain internal registers are implemented in the Data Memory area. These registers ensure correct operation of internal functions such as timers, interrupts, etc., as well as external functions such as I/O data control. The location of these registers within the Data Memory be- gins at the address 00H. Any unused Data Memory lo- cations between these special function registers and the point where the General Purpose Memory begins is re- served and attempting to read data from these locations will return a value of 00H. Indirect Addressing Register - IAR0, IAR1 The Indirect Addressing Registers, IAR0 and IAR1, al- though having their locations in normal RAM register space, do not actually physically exist as normal regis- ters. The method of indirect addressing for RAM data manipulation uses these Indirect Addressing Registers and Memory Pointers, in contrast to direct memory ad- dressing, where the actual memory address is speci- fied. Actions on the IAR0 and IAR1 registers will result in no actual read or write operation to these registers but rather to the memory location specified by their corre- sponding Memory Pointer, MP0 or MP1. Acting as a pair, IAR0 and MP0 can together only access data from Bank 0, while the IAR1 and MP1 register pair can ac- cess data from both Bank 0 and Bank 1. As the Indirect Addressing Registers are not physically implemented, reading the Indirect Addressing Registers indirectly will return a result of ²00H² and writing to the registers indi- rectly will result in no operation. Memory Pointer - MP0, MP1 For all devices, two Memory Pointers, known as MP0 and MP1 are provided. These Memory Pointers are physically implemented in the Data Memory and can be manipulated in the same way as normal registers pro- viding a convenient way with which to address and track data. When any operation to the relevant Indirect Ad- dressing Registers is carried out, the actual address that the microcontroller is directed to, is the address speci- fied by the related Memory Pointer. MP0 can only ac- cess data in Bank 0 while MP1 can access both banks. 0 0 H 0 1 H 0 2 H 0 3 H 0 4 H 0 5 H 0 6 H 0 7 H 0 8 H 0 9 H 0 A H 0 B H 0 C H 0 D H 0 E H 0 F H 1 0 H 1 1 H 1 2 H 1 3 H 1 4 H 1 5 H 1 6 H 1 7 H 1 8 H 1 9 H 1 A H 1 B H 1 C H 1 D H 1 E H 1 F H 2 0 H 2 1 H 2 2 H 2 3 H : U n u s e d r e a d a s " 0 " I A R 0 M P 0 I A R 1 M P 1 B P A C C P C L T B L P T B L H W D T S S T A T U S I N T C T M R 0 T M R 0 C T M R 1 H T M R 1 L T M R 1 C P A P A C P B P B C P C P C C P D P D C P E P E C T B H P U S C U S R S C C 4 0 H 4 1 H 4 2 H 4 3 H 4 4 H 4 5 H 4 6 H 4 7 H 4 8 H 4 9 H 4 A H U S B _ S T A T P I P E _ C T R L A W R S T A L L P I P E S I E S M I S C E N D P T _ E N F I F O 0 F I F O 1 F I F O 2 B a n k 0 B a n k 1 Special Purpose Data Memory |
Similar Part No. - HT82B40R_11 |
|
Similar Description - HT82B40R_11 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.NET |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |