These offset + 2 Byte step for each endpoint.
For example EP0 = +0x00; EP1 = +0x02; or offset+(EPn << 1). In these address space will fit 15 endpoints.
+# 0x80 mUsbFIFOMap FIFO0
+* BIT7
+* BIT6
+* BIT5
+* BIT4 - Direction: 0 - OUT; 1 - IN.
+* BIT0 - BIT3: assigned EP number.
+
+Current layout:
+* 0x80 0x01
+* 0x81 0x01
+* 0x82 0x12
+* 0x83 0x12
+* 0x84 0x05
+* 0x85 0x05
+* 0x86 0x06
+* 0x87 0x06
+* 0x88 0x00
+* 0x89 0x00
+* 0x8a 0x00
+* 0x8b 0x00
+* 0x8c 0x00
+* 0x8d 0x00
+* 0x8e 0x13
+* 0x8f 0x04
+
+# 0x81 mUsbFIFOMap FIFO1
+# 0x82 mUsbFIFOMap FIFO2
+# 0x83 mUsbFIFOMap FIFO3
+# 0x84 mUsbFIFOMap FIFO4
+# 0x85 mUsbFIFOMap FIFO5
+# 0x86 mUsbFIFOMap FIFO6
+# 0x87 mUsbFIFOMap FIFO7
+# 0x88 mUsbFIFOMap FIFO8
+# 0x89 mUsbFIFOMap FIFO9
+# 0x8a mUsbFIFOMap FIFO10
+# 0x8b mUsbFIFOMap FIFO11
+# 0x8c mUsbFIFOMap FIFO12
+# 0x8d mUsbFIFOMap FIFO13
+# 0x8e mUsbFIFOMap FIFO14
+# 0x8f mUsbFIFOMap FIFO15
+
# 0xAE ZM_EP3_BYTE_COUNT_HIGH_OFFSET
BIT3 - 1 xfer done?
comments: after sending data from target to host, set BIT3