Intel Microcontroller manual 8XC196NP, 80C196NU USER’S Manual

8XC196NP, 80C196NU USER’S MANUAL

PTS Single Transfer Mode Control Block (Continued)

Register	Location						Function
PTSCON	PTSCB + 1 PTS Control Bits
		M2:0	PTS Mode
			M2		M1	M0
			1		0	0	single transfer mode
		BW	Byte/Word Transfer
			0	= word transfer
			1	= byte transfer
		SU†	Update PTSSRC

0 = reload original PTS source address after each byte or word transfer

1 = retain current PTS source address after each byte or word transfer

DU† Update PTSDST

	0	=	reload original PTS destination address after each byte or
			word transfer
	1	=	retain current PTS destination address after each byte or
			word transfer
SI†	PTSSRC Autoincrement
	0	= do not increment the contents of PTSSRC after each byte
			or word transfer
	1	= increment the contents of PTSSRC after each byte or word
			transfer
DI†	PTSDST Autoincrement
	0	= do not increment the contents of PTSDST after each byte
			or word transfer
	1	= increment the contents of PTSDST after each byte or word
			transfer

PTSCOUNT PTSCB + 0 Consecutive Word or Byte Transfers

Defines the number of words or bytes that will be transferred during the single transfer routine. Each word or byte transfer is one PTS cycle. Maximum value is 255.

†The DU/DI bits and SU/SI bits are paired in single transfer mode. Each pair must be set or cleared together. However, the two pairs, DU/DI and SU/SI, need not be equal.

Figure 6-12. PTS Control Block — Single Transfer Mode (Continued)

The PTSCB in Table 6-5 defines nine PTS cycles. Each cycle moves a single word from location 20H to an external memory location. The PTS transfers the first word to location 6000H. Then it increments and updates the destination address and decrements the PTSCOUNT register; it does not increment the source address. When the second cycle begins, the PTS moves a second word from location 20H to location 6002H. When PTSCOUNT equals zero, the PTS will have filled locations 6000–600FH, and an end-of-PTS interrupt is ge nerated.

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