Datasheet

Chip-Select Registers
MC68HC812A4 Data Sheet, Rev. 7
Freescale Semiconductor 91
8.6.3 Chip-Select Stretch Registers
Each of the seven chip-selects has a 2-bit field in this register which determines the amount of clock
stretch for accesses in that chip-select space.
Read: Anytime
Write: Anytime
Address: $003E
Bit 7654321Bit 0
Read: 0 0
SRP1A SRP1B SRP0A SRP0B STRDA STRDB
Write:
Reset:00111111
= Unimplemented
Figure 8-18. Chip-Select Stretch Register 0 (CSSTR0)
Address: $003F
Bit 7654321Bit 0
Read:
STR3A STR3B STR2A STR2B STR1A STR1B STR0A STR0B
Write:
Reset:00111111
Figure 8-19. Chip-Select Stretch Register 1 (CSSTR1)
Table 8-4. Stretch Bit Definition
Stretch Bit
SxxxA
Stretch Bit
SxxxB
Number of E-Clocks
Stretched
00 0
01 1
10 2
11 3