Intel 8XC196MD, 8XC196MH, 8XC196MC Auto Programming Mode, Auto Programming Circuit and Memory Map

Models: 8XC196MD 8XC196MH 8XC196MC

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PROGRAMMING THE NONVOLATILE MEMORY

Table 16-10. Timing Mnemonics (Continued)

Mnemonic

Description

 

 

TPHPL

PROG# High to Next PROG# Low.

TPHIL

PROG# High to AINC# Low.

TILIH

AINC# Pulse Width.

TILVH

PVER Hold After AINC# Low.

TILPL

AINC# Low to PROG# Low.

TPHVL

PROG# High to PVER Valid.

16.9 AUTO PROGRAMMING MODE

The auto programming mode is a low-cost programming alternative. Using this programming mode, the device programs itself with data from an external EPROM (external locations 4000H and above; see Table 16-1 on page 16-3). A bank switching mechanism provided by port 1 pins (see Figure 16-12) supports auto programming of devices with more than 16 Kbytes of internal memory.

16.9.1 Auto Programming Circuit and Memory Map

Figure 16-12 shows the recommended circuit for auto programming mode. Table 16-11 shows the 8XC196MC/MD memory map and Table 16-11 shows the 8XC196MH auto programming mem- ory map. Auto programming is specified for a crystal frequency of 6 to 8 MHz. At 8 MHz, use a 27(C)512 EPROM with tACC = 250 ns and tOE = 100 ns or faster specifications.

Tie the BUSWIDTH pin low to configure an 8-bit data bus. Connect P1.3:0 (8XC196MH only) as shown to generate the high-order bits of the external EPROM address. Connect P0.7:4 to VSS and VCC to select auto programming (1100B = 0CH). PACT# and PVER are status outputs, buff- ered by the 74HC14s. They drive LEDs that indicate programming active (PACT#) and program- ming verification (PVER). Connect all unused inputs to ground (VSS) and leave unused outputs floating. READY and NMI are active; connect them as indicated.

NOTE

All external EPROM addresses specified in this section are given for the circuit in Figure 16-12. If you choose a different circuit, you must adjust the addresses accordingly.

16-25

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Intel 8XC196MD, 8XC196MH, 8XC196MC Auto Programming Mode, Auto Programming Circuit and Memory Map, Mnemonic Description