6-26
DSP56309UM/D MOTOROLA
Host Interface (HI08)
HI08-External Host ProgrammerÕs Model
IRQA, IRQB, etc.) and can use any of the reserved or otherwise unused addresses
(provided they have been pre-programmed in the DSP). HV is set to $32 (vector location
$0064) by a hardware RESET signal, software RESET instruction, individual reset, or a
STOP instruction.
6.6.2.2
CVR Host Command Bit (HC) Bit 7
The host processor uses the HC bit to handshake the execution of host command
interrupts. Normally, the host processor sets HC to request a host command interrupt
from the DSP56309. When the DSP56309 acknowledges the host command interrupt, the
HI08 hardware clears the HC bit. The host processor can read the state of HC to
determine when the host command has been accepted. After setting HC, the host must
not write to the CVR again until the HI08 hardware clears HC. Setting the HC bit causes
host command pending (HCP) to be set in the HSR. The host can write to the HC and HV
bits in the same write cycle.
6.6.3
Interface Status Register (ISR)
The interface status register (ISR) is an 8-bit, read-only status register used by the host
processor to interrogate the status and flags of the HI08. The host processor can write to
this address without affecting the internal state of the HI08. The DSP core cannot access
the ISR. The ISR bits are described in the following paragraphs. This register is
illustrated in
6.6.3.1
ISR Receive Data Register Full (RXDF) Bit 0
The RXDF bit indicates that the receive byte registers (RXH:RXM:RXL) contain data
from the DSP56309 and can be read by the host processor. RXDF is set when the HTX is
transferred to the receive byte registers. RXDF is cleared when the receive data (RXL or
RXH according to HLEND bit) register is read by the host processor. RXDF can be
cleared by the host processor using the initialize function. RXDF can assert the external
HREQ signal if the RREQ bit is set. Regardless of whether the RXDF interrupt is enabled,
RXDF indicates whether the RX registers are full and data can be latched out so that the
host processor can use polling techniques.
7
6
5
4
3
2
1
0
HREQ
HF3
HF2
TRDY
TXDE
RXDF
ÑReserved bit. Read as 0. Should be written with 0, for future compatibility.
AA0670
Figure 6-14
Interface Status Register
Summary of Contents for DSP56309
Page 25: ...xxii DSP56309UM D MOTOROLA Figure D 25 Port E Registers PCRE PRRE PDRE D 39 ...
Page 30: ...MOTOROLA DSP56309UM D 1 1 SECTION 1 DSP56309 OVERVIEW ...
Page 47: ...1 18 DSP56309UM D MOTOROLA DSP56309 Overview DSP56309 Architecture Overview ...
Page 48: ...MOTOROLA DSP56309UM D 2 1 SECTION 2 SIGNAL CONNECTION DESCRIPTIONS ...
Page 85: ...2 38 DSP56309UM D MOTOROLA Signal Connection Descriptions OnCE JTAG Interface ...
Page 86: ...MOTOROLA DSP56309UM D 3 1 SECTION 3 MEMORY CONFIGURATION ...
Page 104: ...MOTOROLA DSP56309UM D 4 1 SECTION 4 CORE CONFIGURATION ...
Page 124: ...MOTOROLA DSP56309UM D 5 1 SECTION 5 GENERAL PURPOSE I O ...
Page 125: ...5 2 DSP56309UM D MOTOROLA General Purpose I O 5 1 INTRODUCTION 5 3 5 2 PROGRAMMING MODEL 5 3 ...
Page 128: ...MOTOROLA DSP56309UM D 6 1 SECTION 6 HOST INTERFACE HI08 ...
Page 166: ...MOTOROLA DSP56309UM D 7 1 SECTION 7 ENHANCED SYNCHRONOUS SERIAL INTERFACE ESSI ...
Page 212: ...MOTOROLA DSP56309UM D 8 1 SECTION 8 SERIAL COMMUNICATION INTERFACE SCI ...
Page 241: ...8 30 DSP56309UM D MOTOROLA Serial Communication Interface SCI GPIO Signals and Registers ...
Page 242: ...MOTOROLA DSP56309UM D 9 1 SECTION 9 TRIPLE TIMER MODULE ...
Page 269: ...9 28 DSP56309UM D MOTOROLA Triple Timer Module Timer Operational Modes ...
Page 270: ...MOTOROLA DSP56309UM D 10 1 SECTION 10 ON CHIP EMULATION MODULE ...
Page 302: ...MOTOROLA DSP56309UM D 11 1 SECTION 11 JTAG PORT ...
Page 369: ...C 22 DSP56309UM D MOTOROLA DSP56309 BSDL Listing ...
Page 370: ...MOTOROLA DSP56309UM D D 1 APPENDIX D PROGRAMMING REFERENCE ...
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