z8f1601 ZiLOG Semiconductor, z8f1601 Datasheet - Page 141

• Manufacturer Part Number: z8f1601
• Description: Z8 Encore!? Microcontroller With Flash Memory And 10-bit A/d Converter
• Manufacturer: ZiLOG Semiconductor

PS017609-0803
Configuring DMA0 and DMA1 for Data Transfer
DMA_ADC Operation
Follow these steps to configure and enable DMA0 or DMA1:
1. Write to the DMAx I/O Address register to set the Register File address identifying the
2. Determine the 12-bit Start and End Register File addresses. The 12-bit Start Address
3. Write the Start and End Register File address high nibbles to the DMAx End/Start
4. Write the lower byte of the Start Address to the DMAx Start/Current Address register.
5. Write the lower byte of the End Address to the DMAx End Address register.
6. Write to the DMAx Control register to complete the following:
DMA_ADC transfers data from the ADC to the Register File. The sequence of operations
in a DMA_ADC data transfer is:
1. ADC completes conversion on the current ADC input channel and signals the DMA
2. DMA_ADC requests control of the system bus (address and data) from the eZ8 CPU.
3. After the eZ8 CPU acknowledges the bus request, DMA_ADC transfers the two-byte
4. If the current ADC Analog Input is the highest numbered input to be converted:
on-chip peripheral control register. The upper nibble of the 12-bit address for on-chip
peripheral control registers is always
is given by {DMAx_H[3:0], DMA_START[7:0]}. The 12-bit End Address is given by
{DMAx_H[7:4], DMA_END[7:0]}.
Address High Nibble register.
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controller that two-bytes of ADC data are ready for transfer.
ADC output value to the Register File and then returns system bus control back to the
eZ8 CPU.
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Select loop or single-pass mode operation
Select the data transfer direction (either from the Register File RAM to the on-
chip peripheral control register; or from the on-chip peripheral control register to
the Register File RAM)
Enable the DMAx interrupt request, if desired
Select Word or Byte mode
Select the DMAx request trigger
Enable the DMAx channel
DMA_ADC resets the ADC Analog Input number to 0 and initiates data
conversion on ADC Analog Input 0.
If configured to generate an interrupt, DMA_ADC sends an interrupt request to
the Interrupt Controller
Z8F640x/Z8F480x/Z8F320x/Z8F240x/Z8F160x
FH
. The full address is {FH, DMAx_IO[7:0]}
Direct Memory Access Controller
Z8 Encore!
®
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