SERIES IP1K100 INDUSTRIAL I/O PACK RECONFIGURABLE DIGITAL I/O MODULE
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The address specified in the Memory Address register will be
automatically incremented after the read or write cycle is completed.
Thus, when consecutive locations within the memory are accessed
the Memory Address register need not be manually updated by
software.
Read or write accesses to this register require four wait states.
A software or hardware reset has no affect on this register.
Memory Address Register (Write Only, 16H)
The Memory Address register is used to point to one of 64K
words in memory. The 16 bits of this register are used to specify
one of 64K words that can be accessed via a read or write to the
Memory Data register. Writing to this register is possible via 16-bit
data transfers only.
The address specified in the Memory Address register will be
automatically incremented after the read or write cycle to the Memory
Data register is completed. Thus, when consecutive locations within
the memory are accessed the Memory Address register need not be
manually incremented by software.
A write access to this register requires one wait state. A
software or hardware reset will clear this register to zero.
Clock Generator Shift High Reg (Write Only) - (Base + 18H)
The Clock Generator Shift High Register is a 16-bit write only
register. This is used to set the most significant word of the control
and program values required to control the Cypress ICD2053B
Programmable Clock Generator chip. See the program procedure
example which follows for information on determining the value to
write to this register.
A write access to this register requires eight wait states. A
software or hardware reset has no affect on this register.
Clock Generator Shift Low Register (Write Only) - (Base + 1AH)
The Clock Generator Shift Low Register is a 16-bit write only
register. This is used to set the least significant word of the control
and program values required to control the Cypress ICD2053B
Programmable Clock Generator chip. See the program procedure
example which follows for information on determining the value to
write to this register.
A write access to this register requires eight wait states. A
software or hardware reset has no affect on this register.
Clock Generator Length Register (Write Only) - (Base + 1DH)
The Clock Generator Length Register is an 8-bit write only
register. This register is used to set the length of the control or
program value in both the Clock Generator Shift High and Low
registers. This Length value is used by the hardware to set the
number of clock cycles the Shift High and Shift Low values are
shifted to the Clock Generator chip. See the program procedure
example which follows for information on determining the value to
write to this register.
A write access to this register requires one wait state. A
software or hardware reset will clear the contents of this register to
zero.
Clock Generator Trigger Register (Write Only) - (Base + 1F)
The Clock Generator Trigger Register is an 8-bit write only
register. This register is used to initiate transfer of the control or
program value in the Shift High and Shift Low registers to the Clock
Generator chip.
A write access to this register requires one wait state. A
software or hardware reset has no affect on this register.
Program Procedure to Set Clock Generator Frequency
At power up, the clock generator forces the output frequency to
equal the reference frequency which is 4MHz for an 8MHz carrier
and 16MHz for a 32MHz carrier.
The program word required to set your desired frequency can be
calculated using a program provided by Acromag (BitCalc2k1),
supplied with the EDK. After entering your desired frequency and
then selecting the Calculate button, the Shift High, Shift Low, and
Length register values are calculated and shown. Alternately a
program (BITCALC) is available from Cypress
at
www.cypress.com
. The reference frequency input to the
Cypress ICD2053B is set by the IP1K100 at 4MHz for an 8MHz
carrier and 16MHz for a 32MHz carrier.
1.
Write the control word (14-bits 0x1E05 or 0x1E0D) to the Shift
Low register at Base A 1AH. 0x1E05 selects pin 7 as
an OE input pin with an internal pull-up. 0x1E0D selects pin 7
to multiplex the reference frequency to the CLKOUT pin.
2.
Write the word length (0xE) to the Length register at Base
A 1DH. Note the control word is a 14 bit value.
3.
Write 0x1 to the Trigger register at Base A 1FH to
start the serial shift of the control word to the Clock Generator
chip.
4.
Write the least significant program word to the Shift Low
register at Base A 1AH. Write the most significant
program word to the Shift High register at Base A
18H. Note that the value calculated by the Acromag program
BitCalc2K1 can be used as generated. However, if the
Cypress program is used bit stuffing must be implemented.
5.
Write the length of the program word to the Length register at
Base A 1DH.
6.
Write 0x1 to the Trigger register at Base A 1FH to
start the serial shift of the program word to the Clock Generator
chip.
7.
Write the control word (14-bits 0x1E0C or 0x1E04) to the Shift
Low register at Base A 1AH.
8.
Write the control word (14-bits 0x1E08 or 0x1E00) to the Shift
High register at Base A 18H.
