Date: 19961124 From: Juan Vidal Organization: servicom To: Multiple recipients of list EDESIGN Subject: Re: Q: 80C51FA Int.Vectors ? Leonhard Schneider wrote: > > Hello, > > I was searching for the Interrupt Vector Addresses of the 80C51FA, > rsp. 87C51FA (AKA 8?252 ?), but didn't find a list/table in ANY Data Book. > > In case you have the info or can point to a RELIABLE source of info > about this subject, I'd appreciate your kind/fast response. > > Thanks in advance, Please EXPAND THIS MESSAGE TO FULL SCREEN. >From the INTEL 8XC51FX series handbook: " The C51FX has a total or 7 interrupt vectors: two external interrupts (INT0 and INT1), three timer interrupts (timers 0, 1 , and 2), The PCA interrupt and the serial port interrupt. Interrupt vector Address: INTERRUPT SOURCE INTERRUPT REQUEST BITS CLEARED BY HARDWARE VECTOR ADDRESS ================================================================================= NOT INT0 IE0 No (level) 0003H yes (trans) TIMER 0 TF0 Yes 000BH NOT INT1 IE1 No (level) 0013H Yes(trans) TIMER 1 TF1 Yes 001BH SERIAL PORT RI,TI No 0023H TIMER 2 TF2,EXF2 No 002BH PCA CF,CCFn No 0033H (n = 0-4) IE: Interrupt Enable Register: Address = 0A8H Reset Value= 0000 0000B Bit Addressable EA EC ET2 ES ET1 EX1 ET0 EX0 7 6 5 4 3 2 1 0 EA = Global disable bit. If EA=0, all interrupts are disabled. If EA=1, each interrupt can be individually enabled or disabled by setting or clearing its enable bit. EC = PCA interrupt enable bit ET2= Timer 2 interrupt enable bit ES = Serial Port interrupt enable bit ET1= Timer 1 interrput enable bit EX1= External interrupt 1 enable bit ET0= Timer 0 interrupt enable bit EX0= External interrupt 0 enable bit IP: Interrupt priority registers Address = 0B8H Reset Value= X000 0000B Bit addressable -- PPC PT2 PS PT1 PX1 PT0 PX0 7 6 5 4 3 2 1 0 Priority Bit = 1 assigns high priority Priority Bit = 0 assigns low priority -- = Not implemented, reserved for future use. PPC= PCA interrupt priority bit. PT2= Timer 2 interrupt priority bit PS = Serial port interrupt priority bit PT1= Timer 1 interrupt priority bit PX1= External interrupt 1 priority bit PT0= Timer 0 interrupt priority bit PX0= External interrupt 0 priority bit 8XC51FX interrupt priority structure ------------------------------------ In the 8XC51FX, a second Interrupt Priority register (IPH) has been added, increasing the number of priority levels to four. The added register becomes the MSB of the priority select bits and the existing IP register acts as the LSB. This scheme maintains compatibility with the rest of the MCS-51 family. IPH: Interrupt priority high register Address = 0B7H Reset Value = X000 0000B Not Bit Addressable -- PPCH PT2H PSH PT1H PX1H PT0H PX0H 7 6 5 4 3 2 1 0 -- = Not implemented, reserved for future use PPCH= PCA interrupt priority high bit PT2H= Timer 2 interrupt priority high bit PSH = Serial Port interrupt priority high bit PT1H= Timer 1 interrupt priority high bit PX1H= External interrupt 1 priority high bit PT0H= Timer 0 interrupt priority high bit PX0H= External interrupt priority high bit ================================================================================== I hope this will be useful for you. I've tested this information several times and found no errors, should you have any other problems I've got the original handbook for the MCS-51 family from INTEL. Juan Angel Vidal Pérez