 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
HT95A20P Datasheet(PDF) 11 Page - Holtek Semiconductor Inc |
|
||||||||||||||||||||||||||||||
HT95A20P Datasheet(HTML) 11 Page - Holtek Semiconductor Inc |
|
|
11 / 52 page  HT95LXXX Rev. 1.20 11 May 26, 2004 Special Register, Embedded Control Register, LCD Display Memory and General Purpose RAM BP (RAM Bank) Address Function Description Supported for HT95LXXX 400/P 300/P 200/P 100/P 000/P Special Function Register 00H 00H IAR0 Indirect addressing register 0 ÖÖÖÖÖ 00H 01H MP0 Memory pointer register 0 ÖÖÖÖÖ 00H 02H IAR1 Indirect addressing register 1 ÖÖÖÖÖ 00H 03H MP1 Memory pointer register 1 ÖÖÖÖÖ 00H 04H BP Bank Pointer register ÖÖÖÖÖ 00H 05H ACC Accumulator ÖÖÖÖÖ 00H 06H PCL Program counter lower-order byte register ÖÖÖÖÖ 00H 07H TBLP Table pointer ÖÖÖÖÖ 00H 08H TBLH Table higher-order byte register ÖÖÖÖÖ 00H 09H WDTS Watchdog Timer option setting register ÖÖÖÖÖ 00H 0AH STATUS Status register ÖÖÖÖÖ 00H 0BH INTC0 Interrupt control register 0 ÖÖÖÖÖ 00H 0CH TMR0H Timer/Event Counter 0 high-order byte register ÖÖÖÖÖ Stack Register This is a special part of the memory which is used to save the contents of the program counter only. The stack is organized into 12 levels (HT95L400/40P), 8 lev- els (HT95L300/30P, HT95L200/20P, HT95L100/10P) or 4 levels (HT95L000/00P) and is neither part of the data nor part of the program space, and is neither readable nor writable. The activated level is indexed by the stack pointer (SP) and is neither readable nor writable.Ata subroutine call or interrupt acknowledge signal, the con- tents of the program counter are pushed onto the stack. At the end of a subroutine or an interrupt routine, sig- naled by a return instruction (RET or RETI), the program counter is restored to its previous value from the stack. After a chip reset, the SP will point to the top of the stack. If the stack is full and an interrupt takes place, the inter- rupt request flag will be recorded but the acknowledge signal will be inhibited even if this interrupt is enabled. When the stack pointer is decremented (by RET or RETI), the interrupt will be serviced. This feature pre- vents stack overflow allowing the programmer to use the structure more easily. If the stack is full and a ²CALL² is subsequently executed, stack overflow occurs and the first entry will be lost (only the most recent 12, 8 or 4, de- pending on various MCU type, returned addresses are stored). Data Memory The data memory is divided into four functional groups: special function registers, embedded control register, LCD display memory and general purpose memory. Most are read/write, but some are read only. The special function registers are located from 00H to 1FH. The embedded control registers are located in the memory areas from 20H to 3FH. The remaining spaces which are not specified in the following table before the 40H are reserved for future expanded usage and read- ing these locations will get ²00H². The general purpose data memory is divided into 15 banks (HT95L400/40P), 11 banks (HT95L300/30P), 6 banks (HT95L200/20P, HT95L100/10P) or 2 banks (HT95L000/00P). The banks in the RAM are all addressed from 40H to 0FFH and they are selected by setting the value of the bank pointer (BP). All of the data memory areas can handle arithmetic, logic, increment, decrement and rotate operations di- rectly. Except for some dedicated bits, each bit in the data memory can be set and reset by ²SET [m].i² and ²CLR [m].i². They are also indirectly accessible through memory pointer registers (MP0 or MP1). The bank1~bank14 and bank27 are only indirectly accessi- ble through memory pointer 1 register (MP1). The LCD display memory is located at bank 1BH. They can be read and written to by the indirect addressing mode using memory pointer 1 (MP1). To turn the display On or Off, a ²1² or ²0² is written to the corresponding bit of the memory area. |
Similar Part No. - HT95A20P |
|
Similar Description - HT95A20P |
|
|
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 |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
