AN2131-DK001 Cypress Semiconductor Corp, AN2131-DK001 Datasheet - Page 115

• Manufacturer Part Number: AN2131-DK001
• Description: KIT EZ-USB DEVELOPMENT BOARD
• Manufacturer: Cypress Semiconductor Corp

Specifications of AN2131-DK001

• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 428-1333

2.
3.
Put it anywhere in memory and the jump table in step 1 will automatically jump to it.
In this example, the ISR simply sets the 8051 flag “got_EP2_data” to indicate to the back-
ground program that the endpoint requires service. Note that both data pointers and the
DPS (Data Pointer Select) registers must be saved and restored in addition to the accumu-
lator.
Page 6-18
; -----------------
; Interrupt Vectors
; -----------------
Write the INT2 interrupt vector.
Write the interrupt service routine.
org
ljmp
; -----------------------------
; USB Interrupt Service Routine
; -----------------------------
EP2OUT_ISR
Figure 6-9. Interrupt Service Routine (ISR) for Endpoint 2-OUT
push
push
push
push
push
push
mov
clr
mov
mov
mov
movx
setb
pop
pop
pop
pop
pop
pop
reti
43h
USB_Jump_Table
dps
dpl
dph
dpl1
dph1
acc
a,EXIF
acc.4
EXIF,a
dptr,#OUT07IRQ
a,#01000000b
@dptr,a
got_EP2_data
acc
dph1
dpl1
dph
dpl
dps
Figure 6-8. INT2 Interrupt Vector
Chapter 6. EZ-USB CPU
; save both dptrs, dps, and acc
; clear USB IRQ (INT2)
;
; clear OUT2 int request
; set my flag
; restore vital registers
a “1” clears the IRQ bit
; int2 is the USB vector
; Autovector will replace byte 45
EZ-USB TRM v1.9