diff --git a/dma.py b/dma.py
index 0a06d86..04abead 100644
--- a/dma.py
+++ b/dma.py
@@ -5,12 +5,6 @@ import array
 import uctypes
 from uctypes import BF_POS, BF_LEN, UINT32, BFUINT32, struct
 
-GPIO_BASE       = 0x40014000
-GPIO_CHAN_WIDTH = 0x08
-GPIO_PIN_COUNT  = 30
-PAD_BASE        = 0x4001c000
-PAD_PIN_WIDTH   = 0x04
-ADC_BASE        = 0x4004c000
 PIO0_BASE       = 0x50200000
 PIO1_BASE       = 0x50300000
 DMA_BASE        = 0x50000000
@@ -69,26 +63,11 @@ DMA_REGS = {
     "CHAN_ABORT":         0x444|UINT32
 }
 
-DREQ_PIO0_TX0, DREQ_PIO0_RX0, DREQ_PIO1_TX0 = 0, 4, 8
-DREQ_PIO1_RX0, DREQ_SPI0_TX,  DREQ_SPI0_RX  = 12, 16, 17
-DREQ_SPI1_TX,  DREQ_SPI1_RX,  DREQ_UART0_TX = 18, 19, 20
-DREQ_UART0_RX, DREQ_UART1_TX, DREQ_UART1_RX = 21, 22, 23
-DREQ_I2C0_TX,  DREQ_I2C0_RX,  DREQ_I2C1_TX  = 32, 33, 34
-DREQ_I2C1_RX,  DREQ_ADC                     = 35, 36
-
-
-
 DMA_CHANS = [struct(DMA_BASE + n*DMA_CHAN_WIDTH, DMA_CHAN_REGS) for n in range(0,DMA_CHAN_COUNT)]
 DMA_DEVICE = struct(DMA_BASE, DMA_REGS)
 
-
-GPIO_FUNC_SPI, GPIO_FUNC_UART, GPIO_FUNC_I2C = 1, 2, 3
-GPIO_FUNC_PWM, GPIO_FUNC_SIO, GPIO_FUNC_PIO0 = 4, 5, 6
-GPIO_FUNC_NULL = 0x1f
-
 DMA_CH0_AL3_TRANS_COUNT = DMA_BASE + 0x38
 
-
 class PIO_DMA_Transfer():
     def __init__(self, dma_channel, sm_num, block_size, transfer_count):
         self.dma_chan = DMA_CHANS[dma_channel]
@@ -127,66 +106,12 @@ class PIO_DMA_Transfer():
         else:
             return False
         
-    def abort_transfer(self):
-        pass
-    
-    def chain_to(self, channel):
-        self.dma_chan.CTRL_TRIG.CHAIN_TO = channel
-        
-    def get_number(self):
-        return self.channel_number
+
         
 
 
-    
-#looping transfers
-#note -- see datasheet 2.5.7
-#location of registers is -- AL3 transcount / read address trigger.
-#Writing to these (from one DMA channel) will re-trigger a second DMA channel
-#need to set write ring.
-#could also set read ring?
-#out_buff = array.array('L', ((x if (x<1000) else (2000-x)) for x in range(NSAMPLES)))
 
-class DMA_Control_Block:
-    def __init__(self, this_chan, that_chan, read_address, transfer_count, loops):
-        self.dma_chan = DMA_CHANS[this_chan]
-        
-        #note -- need to set this up to get the right location
-        #but for now just always control channel 0
-        self.dma_chan.WRITE_ADDR_REG = DMA_CH0_AL3_TRANS_COUNT
-        self.dma_chan.CTRL_TRIG.DATA_SIZE = DMA_SIZE_WORD
-        self.dma_chan.TRANS_COUNT_REG = 2 # two transfers. One is the count, one is the read_address.
-        #Then pauses until the other channel chains back to this.
-        
-        self.buffer = array.array('L', (x for x in range(2*loops)))
-        for x in range(loops):
-            self.buffer[2*x] = transfer_count
-            self.buffer[2*x+1] = read_address
-            
-        self.start_address = uctypes.addressof(self.buffer)
-        #set up read ring
-        that_chan.chain_to(this_chan)
-        
-        self.dma_chan.CTRL_TRIG.INCR_WRITE = 1
-        self.dma_chan.CTRL_TRIG.INCR_READ = 1
-        
-        self.dma_chan.CTRL_TRIG.RING_SEL = 1
-        self.dma_chan.CTRL_TRIG.RING_SIZE = 3 # 1u<<3 bytes / 8 bytes
-        self.dma_chan.CTRL_TRIG.TREQ_SEL = 0x3f # unpaced transfer
-        
-    def start_chain(self):
-        self.dma_chan.READ_ADDR_REG = self.start_address
-        self.dma_chan.CTRL_TRIG.EN = 1
-        
-    def transfer_count(self):
-        return self.dma_chan.TRANS_COUNT_REG
-    
-    def get_read_address(self):
-        return self.dma_chan.READ_ADDR_REG
-    
-    def busy(self):
-        if self.dma_chan.CTRL_TRIG.DATA_SIZE == 1:
-            return True
-        else:
-            return False
+
+
+