8 / 36 page CY7C63411/12/13 CY7C63511/12/13 CY7C63612/13 FOR FOR Document #: 38-08027 Rev. ** Page 8 of 36 4.0 Programming Model 4.1 14-bit Program Counter (PC) The 14-bit Program Counter (PC) allows access for up to 8 kilobytes of EPROM using the CY7C634XX/5XX/6XX architecture. The program counter is cleared during reset, such that the first instruction executed after a reset is at address 0x0000h. This is typically a jump instruction to a reset handler that initializes the application. The lower eight bits of the program counter are incremented as instructions are loaded and executed. The upper six bits of the program counter are incremented by executing an XPAGE instruction. As a result, the last instruction executed within a 256-byte “page” of sequential code should be an XPAGE instruction. The assembler directive “XPAGEON” will cause the assembler to insert XPAGE instructions automatically. As instructions can be either one or two bytes long, the assembler may occasionally need to insert a NOP followed by an XPAGE for correct execution. The program counter of the next instruction to be executed, carry flag, and zero flag are saved as two bytes on the program stack during an interrupt acknowledge or a CALL instruction. The program counter, carry flag, and zero flag are restored from the program stack only during a RETI instruction. Please note the program counter cannot be accessed directly by the firmware. The program stack can be examined by reading SRAM from location 0x00 and up. 4.2 8-bit Accumulator (A) The accumulator is the general purpose, do everything register in the architecture where results are usually calculated. 4.3 8-bit Index Register (X) The index register “X” is available to the firmware as an auxiliary accumulator. The X register also allows the processor to perform indexed operations by loading an index value into X. 3.0 Pin Assignments Name I/O CY7C63411/12/13 CY7C635 11/12/13 CY7C636 12/13 Description 40-Pin 48-Pin 48-Pin 24-Pin D+, D– I/O 1,2 1,2 1,2 1,2 USB differential data; PS/2 clock and data signals P0[7:0] I/O 15,26,16, 25,17,24, 18,23 17,32,18, 31,19,30, 20,29 17,32,18, 31,19,30, 20,29 7,18,8, 17,9,16, 10,15 GPIO port 0 capable of sinking 7 mA (typical) P1[3:0] I/O 11,30,12, 29,13,28, 14,27 11,38,12, 37,13,36, 14,35 11,38,12, 37,13,36, 14,35 5,20,6, 19 GPIO Port 1 capable of sinking 7 mA (typical). P1[7:4] not bonded out on CY7C63612/13. See note on page 17 for firmware code needed for unused pins. P2 I/O 7,34,8, 33,9,32, 10,31 7,42,8, 41,9,40, 10,39 7,42,8, 41,9,40, 10,39 n/a GPIO Port 2 not bonded out on CY7C63612/13. See note on page 17 for firmware code needed for unused pins. P3[7:4] I/O 3,38,4, 37,5,36, 6,35 3,46,4, 45,5,44, 6,43 3,46,4, 45,5,44, 6,43 3,22,4, 21 GPIO Port 3 capable of sinking 12 mA (typical). P3[3:0] not bonded out on CY7C63612/13. See note on page 17 for firmware code needed for unused pins. DAC I/O n/a n/a 15,34,16, 33,21,28, 22,27 n/a DAC I/O Port with programmable current sink outputs. DAC[1:0] offer a programmable range of 3.2 to 16 mA typical. DAC[7:2] have a programmable sink current range of 0.2 to 1.0 mA typical. DAC I/O Port not bonded out on CY7C63612/13. See note on page 17 for firmware code needed for unused pins. XTALIN IN 21 25 25 13 6-MHz ceramic resonator or external clock input XTALOUT OUT 22 26 26 14 6-MHz ceramic resonator VPP 19 23 23 11 Programming voltage supply, ground during operation VCC 40 48 48 24 Voltage supply Vss 20,39 24,47 24,47 12,23 Ground |
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