MCP402XEV Microchip Technology, MCP402XEV Datasheet - Page 44

• Manufacturer Part Number: MCP402XEV
• Description: BOARD EVAL FOR MCP402X
• Manufacturer: Microchip Technology

Specifications of MCP402XEV

• Main Purpose: Digital Potentiometer
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: MCP4021
• Primary Attributes: 1 Single Pot, 10 kOhm, 64 Tap, Non Volatile
• Secondary Attributes: 2.7 ~ 5.5 V, 150 ppm/°C
• Processor To Be Evaluated: MCP402X
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

TABLE E-1:
© 2005 Microchip Technology Inc.
DLOOP_HVIWL
HV_Decrement_WL_Enable
DLOOP_HVDWL
;***********************************************************************************************
; VARIABLE DELAY SUBROUTINES
;***********************************************************************************************
;
;
;
; ex. To create a 300ms delay when using a 4Mhz osc, 300-250 = 50
;
;
;
;
;************
; The value in W at the time of the CALL = x.
VAR1000TcyDELAY
DLOOP2
DLOOP1
clrwdt
nop
decfsz
goto
bcf
goto
bsf
goto
bcf
goto
bcf
bcf
goto
bsf
retlw
bcf
bsf
goto
bsf
movlw
movwf
clrwdt
nop
decfsz
goto
bsf
goto
bcf
bcf
goto
bsf
retlw
DLYCNT1 = F9h = 249d
DELAY = T((4 DLYCNT1 + 4) DLYCNT2 + 4)
movlw .50
call
call
movwf
movlw
movwf
clrwdt
decfsz
goto
decfsz
goto
retlw
VAR1000TcyDELAY ;call VAR1000TcyDELAY = 50ms delay w/4MHz Osc
VAR1000TcyDELAY ;call VAR1000TcyDELAY = 250ms delay w/4MHz Osc
;total = 300ms delay
DLYCNT1,f
DLOOP_HVIWL
UD
$+1
UD
$+1
UD
$+1
HV_CS
CS
$+1
CS
0x04
UD
CS
$+1
HV_CS
.100
DLYCNT1
DLYCNT1,f
DLOOP_HVDWL
UD
$+1
HV_CS
CS
$+1
CS
0x05
DLYCNT2
.249
DLYCNT1
DLYCNT1,f
DLOOP1
DLYCNT2,f
DLOOP2
.250
;or NOP
;or NOP
;or NOP
00066_MCP402XEV.ASM SOURCE CODE (CONTINUED)
;load .50 into WREG
; creates a 3us total delay
; creates a 3us total delay
; creates a 3us total delay
; shut off 1Mhz Charge Pump
; helps pull the signal down from HV
; Follow w/long delay to discharge pump & EEPROM Write Cycle
; creates a 3us total delay
; starts 1Mhz Charge Pump
; 5*100 = 500us delay for Charge Pump ramp time
; creates a 3us total delay
; shut off 1Mhz Charge Pump
; helps pull the signal down from HV
; Follow w/long delay to discharge pump & EEPROM Write Cycle
DLYCNT2 = W
00066_MCP402XEV.ASM Source Code
; LOADS CONTROLLING DLY # INTO PRIMARY COUNTER
; MAXIMIZES THE SECONDARY DLY COUNTER
; DECREMENT AND TEST SECONDARY LOOP FOR ZERO
; CONTINUE SECONDARY LOOP
; DECREMENT AND TEST PRIMARY DLY COUNTER
; CONTINUE PRIMARY LOOP
; preload W for the next CALL VAR1000TcyDELAY
Delay = 1000Tcy*x
DS51546B-page 40