PROGRAMMING THE NONVOLATILE MEMORY

Figure 16-14 shows the recommended circuit for PCCB and UPROM programming. In these cir- cuits, the PBUS holds data to be written to the OTPROM, PALE# begins programming, and PVER drives an LED that lights to indicate successful programming.

 

 

 

 

VCC

 

20 pF

 

 

20 pF

 

 

 

XTAL1

XTAL2

 

100 kΩ

 

 

 

 

 

 

VCC

RESET#

 

 

Reset

+5.0V

V

 

 

1 kΩ

1.0µF

 

CC

74HC14

 

 

READY/P5.6

 

 

VSS

 

10µF

 

 

 

 

 

 

NMI

 

 

 

 

BUSWIDTH/P5.7

 

 

 

 

EA#

 

 

 

 

+12.50V

VPP

 

 

VCC

 

VCC

 

 

 

 

 

 

 

 

 

 

VREF

 

 

10kΩ

 

 

 

 

 

 

SW1

 

 

Pullups Required

 

 

P0.7

 

 

 

 

P4.7 – P3.0

 

 

P0.6

 

 

 

 

 

P0.5

P4.7:0

 

 

 

 

P0.4

 

 

 

 

 

P0.3:0

 

 

 

 

PMODE = 0DH PCCB Mode

P1.4:0

 

 

 

 

 

 

 

 

 

PMODE = 09H UPROM Mode

P2.5:2

P3.7:0

SW2

PCCB/UPROM

 

 

ANGND

 

 

Value

 

 

 

 

 

VCC

 

 

 

 

 

 

P2.1/PALE#

 

 

 

10kΩ

 

 

 

 

 

Push to Program

 

 

 

 

 

270kΩ

 

 

 

 

 

 

P2.0/PVER

 

 

 

74HC14

87C196 Device

 

 

 

 

 

 

 

 

A3003-02

Figure 16-14. PCCB and UPROM Programming Circuit

To enter either mode, follow the standard power-up sequence (page 16-14) after setting the values listed in Table 16-13. If you want to program both the PCCB and the UPROM bits, program one of them and complete the power-down sequence. Then reconfigure the PMODE and port 3 pins and repeat the power-up sequence.

16-31

Page 384
Image 384
Intel 8XC196MD, 8XC196MH, 8XC196MC manual Pccb and Uprom Programming Circuit