XC68HC705JJ7 Motorola, XC68HC705JJ7 Datasheet - Page 180

• Manufacturer Part Number: XC68HC705JJ7
• Description: MICROCONTROLLER
• Manufacturer: Motorola

Personality EPROM (PEPROM)
12.5 PEPROM Reading
Advance Information
180
NOTE:
The PEPROM can also be programmed by user software with the V
voltage level applied to the IRQ/V
program each PEPROM bit:
This sequence shows how to read the PEPROM:
Reading the PEPROM is easiest when each PEPROM column contains
one byte. Selecting a row 0 bit selects the first bit, and incrementing the
PEPROM bit select register (PEBSR) selects the next bit in row 1 from
the same column. Incrementing PEBSR seven more times selects the
remaining bits of the column and ends up selecting the bit in row 0 of the
next column, thereby setting the row 0 flag, PEPRZF.
A PEPROM byte that has been read can be transferred to the personality
EPROM bit select register (PEBSR) as a temporary storage location
such that subsequent reads of the PEBSR quickly yield that PEPROM
byte.
1. Select a PEPROM bit by writing to the PEBSR.
2. Set the PEPGM bit in the PESCR.
3. Wait for the programming time, t
4. Clear the PEPGM bit.
5. Move to next PEPROM bit to be programmed in step 1.
1. Select a bit by writing to the PEBSR.
2. Read the PEDATA bit in the PESCR.
3. Store the PEDATA bit in RAM or in a register.
4. Select another bit by changing the PEBSR.
5. Continue reading and storing the PEDATA bits until the required
personality EPROM data is retrieved and stored.
Personality EPROM (PEPROM)
MC68HC705JJ7 • MC68HC705JP7 — REV 4
PP
pin. This sequence shows how to
EPGM
.
MOTOROLA
PP